diff --git a/src/integration-test/kotlin/de/bixilon/minosoft/data/accounts/types/test/TestAccount.kt b/src/integration-test/kotlin/de/bixilon/minosoft/data/accounts/types/test/TestAccount.kt
new file mode 100644
index 000000000..12c064081
--- /dev/null
+++ b/src/integration-test/kotlin/de/bixilon/minosoft/data/accounts/types/test/TestAccount.kt
@@ -0,0 +1,40 @@
+/*
+ * Minosoft
+ * Copyright (C) 2020-2023 Moritz Zwerger
+ *
+ * This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * This software is not affiliated with Mojang AB, the original developer of Minecraft.
+ */
+
+package de.bixilon.minosoft.data.accounts.types.test
+
+import de.bixilon.kutil.latch.CountUpAndDownLatch
+import de.bixilon.kutil.uuid.UUIDUtil.toUUID
+import de.bixilon.minosoft.data.accounts.Account
+import de.bixilon.minosoft.data.accounts.AccountStates
+import de.bixilon.minosoft.data.entities.entities.player.properties.PlayerProperties
+import de.bixilon.minosoft.data.registries.identified.Namespaces.minosoft
+import de.bixilon.minosoft.data.registries.identified.ResourceLocation
+import java.util.*
+
+object TestAccount : Account("Bixilon") {
+    override val id: String = "id"
+    override val type: ResourceLocation = minosoft("test_account")
+    override val properties: PlayerProperties? = null
+    override val uuid: UUID = "9e6ce7c5-40d3-483e-8e5a-b6350987d65f".toUUID()
+    override var state: AccountStates
+        get() = AccountStates.WORKING
+        set(value) {}
+    override val supportsSkins: Boolean get() = true
+
+    override fun join(serverId: String) = Unit
+
+    override fun logout(clientToken: String) = Unit
+
+    override fun check(latch: CountUpAndDownLatch?, clientToken: String) = Unit
+}
diff --git a/src/integration-test/kotlin/de/bixilon/minosoft/data/chat/signature/SignatureSIT.kt b/src/integration-test/kotlin/de/bixilon/minosoft/data/chat/signature/SignatureSIT.kt
index c6568e78e..a479732da 100644
--- a/src/integration-test/kotlin/de/bixilon/minosoft/data/chat/signature/SignatureSIT.kt
+++ b/src/integration-test/kotlin/de/bixilon/minosoft/data/chat/signature/SignatureSIT.kt
@@ -1,6 +1,6 @@
 /*
  * Minosoft
- * Copyright (C) 2020-2022 Moritz Zwerger
+ * Copyright (C) 2020-2023 Moritz Zwerger
  *
  * This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
  *
@@ -20,9 +20,11 @@ import de.bixilon.minosoft.util.yggdrasil.YggdrasilUtil
 import org.testng.Assert
 import org.testng.SkipException
 import org.testng.annotations.Test
+import java.time.Instant
 
 @Test(groups = ["private_key"])
 class SignatureSIT {
+    // The private key is a private environment variable in gitlab. Yes, that makes it hard to run tests outside my devices, but you have to understand that I am not publishing my private key, no matter if it is already expired
 
     fun loadYggdrasil() {
         YggdrasilUtil.load()
@@ -35,12 +37,17 @@ class SignatureSIT {
 
     @Test(dependsOnMethods = ["loadPrivateKey"])
     fun testKeyUUID() {
-        SignatureTestUtil.key.requireSignature("9e6ce7c5-40d3-483e-8e5a-b6350987d65f".toUUID()) // yep, that is really my private key
+        SignatureTestUtil.key.requireSignature("9e6ce7c5-40d3-483e-8e5a-b6350987d65f".toUUID()) // yep, that is really Bixilon's private key
     }
 
     @Test(dependsOnMethods = ["loadPrivateKey"])
     fun testRequireSignature() {
-        Assert.assertThrows { SignatureTestUtil.key.requireSignature("b876ec32-e396-476b-a115-8438d83c67d4".toUUID()) }
+        Assert.assertThrows { SignatureTestUtil.key.requireSignature("b876ec32-e396-476b-a115-8438d83c67d4".toUUID()) } // sadly that is not possible anymore
+    }
+
+    @Test(dependsOnMethods = ["loadPrivateKey"])
+    fun testExpiresAt() {
+        Assert.assertEquals(SignatureTestUtil.key.expiresAt, Instant.ofEpochSecond(1668977246L, 93031788L)) // verify that we load the correct key and not just some key
     }
 }
 
diff --git a/src/integration-test/kotlin/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner1Test.kt b/src/integration-test/kotlin/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner1Test.kt
new file mode 100644
index 000000000..985bc45a3
--- /dev/null
+++ b/src/integration-test/kotlin/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner1Test.kt
@@ -0,0 +1,85 @@
+/*
+ * Minosoft
+ * Copyright (C) 2020-2023 Moritz Zwerger
+ *
+ * This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * This software is not affiliated with Mojang AB, the original developer of Minecraft.
+ */
+
+package de.bixilon.minosoft.data.chat.signature.signer
+
+import de.bixilon.kutil.base64.Base64Util.fromBase64
+import de.bixilon.minosoft.data.accounts.types.test.TestAccount
+import de.bixilon.minosoft.data.chat.signature.SignatureTestUtil
+import de.bixilon.minosoft.protocol.protocol.ProtocolVersions
+import de.bixilon.minosoft.protocol.versions.Version
+import de.bixilon.minosoft.protocol.versions.Versions
+import org.testng.annotations.Test
+import org.testng.internal.junit.ArrayAsserts.assertArrayEquals
+import java.time.Instant
+
+@Test(groups = ["signature"], dependsOnGroups = ["private_key"])
+class MessageSigner1Test {
+    private lateinit var version: Version
+
+    @Test(priority = -1)
+    fun setup() {
+        version = Versions.getById(ProtocolVersions.V_1_19)!!
+    }
+
+    private fun create(): MessageSigner1 {
+        return MessageSigner1(version)
+    }
+
+    fun signing1() {
+        val message = "bixilon began the development during lockdown"
+        val time = Instant.ofEpochMilli(1673102470_1234)
+        val signer = create()
+        val signature = signer.signMessage(SignatureTestUtil.key.pair.private, message, -4886770986649219020L, TestAccount.uuid, time)
+
+
+        val expected = "".fromBase64() // TODO
+        assertArrayEquals(expected, signature)
+    }
+
+    fun signing2() {
+        val message = "reversing signature code is pita"
+        val time = Instant.ofEpochMilli(1673103191_5678)
+        val signer = create()
+        val signature = signer.signMessage(SignatureTestUtil.key.pair.private, message, 1856442944183750824L, TestAccount.uuid, time)
+
+
+        val expected = "".fromBase64() // TODO
+        assertArrayEquals(expected, signature)
+    }
+
+    fun signing3() {
+        val message = "now even with last seen messages. I don't know their purpose."
+        val time = Instant.ofEpochMilli(1673103854_8402)
+        val signer = create()
+
+        val signature = signer.signMessage(SignatureTestUtil.key.pair.private, message, 6392082609L, TestAccount.uuid, time)
+
+
+        val expected = "".fromBase64() // TODO
+        assertArrayEquals(expected, signature)
+    }
+
+    fun signing4() {
+        val message = "ʞ⍧\uDB16\uDFB1іⴎO\uD85E\uDF9A!㛽J˻5&뻝\uD8B9\uDE8F\uDA0C\uDC41\uDB9B\uDD0Fi읣މ猣랒糓\uD8EF\uDFCFk\uDA1D\uDCA4썿ߛ믣Ȣ\uDA51\uDF5B4" // random utf8 chars
+        val time = Instant.ofEpochMilli(1739579479_6302)
+        val signer = create()
+
+        val signature = signer.signMessage(SignatureTestUtil.key.pair.private, message, 6392082609L, TestAccount.uuid, time)
+
+
+        val expected = "".fromBase64() // TODO
+        assertArrayEquals(expected, signature)
+    }
+    // TODO: Test 22w17a (sha1 signature)
+}
diff --git a/src/integration-test/kotlin/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner2Test.kt b/src/integration-test/kotlin/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner2Test.kt
new file mode 100644
index 000000000..4cac6c610
--- /dev/null
+++ b/src/integration-test/kotlin/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner2Test.kt
@@ -0,0 +1,92 @@
+/*
+ * Minosoft
+ * Copyright (C) 2020-2023 Moritz Zwerger
+ *
+ * This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * This software is not affiliated with Mojang AB, the original developer of Minecraft.
+ */
+
+package de.bixilon.minosoft.data.chat.signature.signer
+
+import de.bixilon.kutil.base64.Base64Util.fromBase64
+import de.bixilon.minosoft.data.accounts.types.test.TestAccount
+import de.bixilon.minosoft.data.chat.signature.LastSeenMessageList
+import de.bixilon.minosoft.data.chat.signature.SignatureTestUtil
+import de.bixilon.minosoft.data.chat.signature.lastSeen.LastSeenMessage
+import de.bixilon.minosoft.protocol.protocol.ProtocolVersions
+import de.bixilon.minosoft.protocol.versions.Version
+import de.bixilon.minosoft.protocol.versions.Versions
+import org.testng.annotations.Test
+import org.testng.internal.junit.ArrayAsserts.assertArrayEquals
+import java.time.Instant
+import java.util.*
+
+@Test(groups = ["signature"], dependsOnGroups = ["private_key"])
+class MessageSigner2Test {
+    private lateinit var version: Version
+
+    @Test(priority = -1)
+    fun setup() {
+        version = Versions.getById(ProtocolVersions.V_1_19_2)!!
+    }
+
+    private fun create(): MessageSigner2 {
+        return MessageSigner2(version)
+    }
+
+    fun signing1() {
+        val message = "bixilon began the development during lockdown"
+        val time = Instant.ofEpochMilli(1673102470_1234)
+        val signer = create()
+        val signature = signer.signMessage(SignatureTestUtil.key.pair.private, message, null, -4886770986649219020L, TestAccount.uuid, time, LastSeenMessageList(emptyArray()))
+
+
+        val expected = "".fromBase64() // TODO
+        assertArrayEquals(expected, signature)
+    }
+
+    fun signing2() {
+        val message = "reversing signature code is pita"
+        val time = Instant.ofEpochMilli(1673103191_5678)
+        val signer = create()
+        val signature = signer.signMessage(SignatureTestUtil.key.pair.private, message, null, 1856442944183750824L, TestAccount.uuid, time, LastSeenMessageList(emptyArray()))
+
+
+        val expected = "".fromBase64() // TODO
+        assertArrayEquals(expected, signature)
+    }
+
+    fun signing3() {
+        val message = "now even with last seen messages. I don't know their purpose."
+        val time = Instant.ofEpochMilli(1673103854_8402)
+        val signer = create()
+
+        val lastSeen = LastSeenMessageList(arrayOf(LastSeenMessage(UUID(0L, 0L), "/OmblHW9CwdAawdE7WtVurRs7umsa/my8EeTT/NY36lqg3HmtAsqyRQ4fXHelw6pOA4o8UroAlmx+inwiEFHXkDICEIVM69vHKapQvoAaeEVrQ4pn9vURTY3GcUVOgr12V3d00odEpwviXaF6kchG1b/pZsLsfpacMiiVHkxZoqolvUNifHQKXVS48Gu1AKkwRw6bkcOKYZpcZgffe6U273rEQQefwzIdT/8F1P04WhiH7SREexVOolkuoKo6gYxXELf5M0BUf0ssG3SS1k8Wr3ys9nzB6hSoEd/ftKqGVxoqeq7pd1GgKfaRWpka8ZNyDpdm8JqvrmlN/phpS5X4Q==".fromBase64()))) // uuid does not matter, bytes are random
+        val signature = signer.signMessage(SignatureTestUtil.key.pair.private, message, null, 6392082609L, TestAccount.uuid, time, lastSeen)
+
+
+        val expected = "".fromBase64() // TODO
+        assertArrayEquals(expected, signature)
+    }
+
+    fun signing4() {
+        val message = "ʞ⍧\uDB16\uDFB1іⴎO\uD85E\uDF9A!㛽J˻5&뻝\uD8B9\uDE8F\uDA0C\uDC41\uDB9B\uDD0Fi읣މ猣랒糓\uD8EF\uDFCFk\uDA1D\uDCA4썿ߛ믣Ȣ\uDA51\uDF5B4" // random utf8 chars
+        val time = Instant.ofEpochMilli(1739579479_6302)
+        val signer = create()
+
+        val signature = signer.signMessage(SignatureTestUtil.key.pair.private, message, null, 6392082609L, TestAccount.uuid, time, LastSeenMessageList(emptyArray()))
+
+
+        val expected = "".fromBase64() // TODO
+        assertArrayEquals(expected, signature)
+    }
+
+    // TODO: Test 1.19.1 (changes to string encoding)
+    // TODO: Test preview
+    // TODO: Test previous signature (singing 2x)
+}
diff --git a/src/integration-test/kotlin/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner3Test.kt b/src/integration-test/kotlin/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner3Test.kt
new file mode 100644
index 000000000..6c99503ed
--- /dev/null
+++ b/src/integration-test/kotlin/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner3Test.kt
@@ -0,0 +1,122 @@
+/*
+ * Minosoft
+ * Copyright (C) 2020-2023 Moritz Zwerger
+ *
+ * This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ * This software is not affiliated with Mojang AB, the original developer of Minecraft.
+ */
+
+package de.bixilon.minosoft.data.chat.signature.signer
+
+import de.bixilon.kutil.base64.Base64Util.fromBase64
+import de.bixilon.kutil.uuid.UUIDUtil.toUUID
+import de.bixilon.minosoft.data.accounts.types.test.TestAccount
+import de.bixilon.minosoft.data.chat.signature.LastSeenMessageList
+import de.bixilon.minosoft.data.chat.signature.SignatureTestUtil
+import de.bixilon.minosoft.data.chat.signature.lastSeen.LastSeenMessage
+import de.bixilon.minosoft.protocol.protocol.ProtocolVersions
+import de.bixilon.minosoft.protocol.versions.Version
+import de.bixilon.minosoft.protocol.versions.Versions
+import org.testng.Assert.assertEquals
+import org.testng.annotations.Test
+import org.testng.internal.junit.ArrayAsserts.assertArrayEquals
+import java.time.Instant
+import java.util.*
+
+@Test(groups = ["signature"], dependsOnGroups = ["private_key"])
+class MessageSigner3Test {
+    private lateinit var version: Version
+
+    @Test(priority = -1)
+    fun setup() {
+        version = Versions.getById(ProtocolVersions.V_1_19_3)!!
+    }
+
+    private fun create(sessionId: UUID): MessageSigner3 {
+        return MessageSigner3(version, sessionId)
+    }
+
+    fun signing1() {
+        val message = "bixilon began the development during lockdown"
+        val time = Instant.ofEpochMilli(1673102470_1234)
+        val signer = create("a26b7114-36c4-4eea-acac-108f516ef72d".toUUID())
+        val signature = signer.signMessage(SignatureTestUtil.key.pair.private, message, -4886770986649219020L, TestAccount.uuid, time, LastSeenMessageList(emptyArray()))
+
+
+        val expected = "".fromBase64() // TODO
+        assertArrayEquals(expected, signature)
+    }
+
+    fun signing2() {
+        val message = "reversing signature code is pita"
+        val time = Instant.ofEpochMilli(1673103191_5678)
+        val signer = create("79f3da83-a6a1-4d55-9aca-39d5faf4ad8b".toUUID())
+        val signature = signer.signMessage(SignatureTestUtil.key.pair.private, message, 1856442944183750824L, TestAccount.uuid, time, LastSeenMessageList(emptyArray()))
+
+
+        val expected = "".fromBase64() // TODO
+        assertArrayEquals(expected, signature)
+    }
+
+    fun signing3() {
+        val message = "now even with last seen messages. I don't know their purpose."
+        val time = Instant.ofEpochMilli(1673103854_8402)
+        val signer = create("5c31705b-963c-4832-b8a5-1ee617a4b362".toUUID())
+
+        val lastSeen = LastSeenMessageList(arrayOf(LastSeenMessage(UUID(0L, 0L), "/OmblHW9CwdAawdE7WtVurRs7umsa/my8EeTT/NY36lqg3HmtAsqyRQ4fXHelw6pOA4o8UroAlmx+inwiEFHXkDICEIVM69vHKapQvoAaeEVrQ4pn9vURTY3GcUVOgr12V3d00odEpwviXaF6kchG1b/pZsLsfpacMiiVHkxZoqolvUNifHQKXVS48Gu1AKkwRw6bkcOKYZpcZgffe6U273rEQQefwzIdT/8F1P04WhiH7SREexVOolkuoKo6gYxXELf5M0BUf0ssG3SS1k8Wr3ys9nzB6hSoEd/ftKqGVxoqeq7pd1GgKfaRWpka8ZNyDpdm8JqvrmlN/phpS5X4Q==".fromBase64()))) // uuid does not matter, bytes are random
+        val signature = signer.signMessage(SignatureTestUtil.key.pair.private, message, 6392082609L, TestAccount.uuid, time, lastSeen)
+
+
+        val expected = "".fromBase64() // TODO
+        assertArrayEquals(expected, signature)
+    }
+
+    fun signing4() {
+        val message = "ʞ⍧\uDB16\uDFB1іⴎO\uD85E\uDF9A!㛽J˻5&뻝\uD8B9\uDE8F\uDA0C\uDC41\uDB9B\uDD0Fi읣މ猣랒糓\uD8EF\uDFCFk\uDA1D\uDCA4썿ߛ믣Ȣ\uDA51\uDF5B4" // random utf8 chars
+        val time = Instant.ofEpochMilli(1739579479_6302)
+        val signer = create("232170f7-ef39-4959-bf4a-354145b9483a".toUUID())
+
+        val signature = signer.signMessage(SignatureTestUtil.key.pair.private, message, 6392082609L, TestAccount.uuid, time, LastSeenMessageList(emptyArray()))
+
+
+        val expected = "".fromBase64() // TODO
+        assertArrayEquals(expected, signature)
+    }
+
+    fun signing5() {
+        val messages = listOf(
+            Pair(
+                "this is the first message :)",
+                Instant.ofEpochMilli(1673104584_7491),
+            ),
+            Pair(
+                "this is the second message :)",
+                Instant.ofEpochMilli(1673104585_7492),
+            ),
+            Pair(
+                "this is the third and last message :)",
+                Instant.ofEpochMilli(1673104586_7493),
+            )
+        )
+
+        val signer = create("de2f95c2-8730-47ba-a5aa-8db09fcec48e".toUUID())
+
+        val signatures: MutableList<ByteArray> = mutableListOf()
+        for ((message, time) in messages) {
+            signatures += signer.signMessage(SignatureTestUtil.key.pair.private, message, 6392082609L, TestAccount.uuid, time, LastSeenMessageList(emptyArray()))
+        }
+
+
+        val expected = listOf(
+            "".fromBase64(), // TODO
+            "".fromBase64(), // TODO
+            "".fromBase64(), // TODO
+        )
+        assertEquals(expected, signatures)
+    }
+}
diff --git a/src/integration-test/kotlin/de/bixilon/minosoft/data/registries/versions/PixLyzerLoadingTest.kt b/src/integration-test/kotlin/de/bixilon/minosoft/data/registries/versions/PixLyzerLoadingTest.kt
index d88be3214..9683f4ab0 100644
--- a/src/integration-test/kotlin/de/bixilon/minosoft/data/registries/versions/PixLyzerLoadingTest.kt
+++ b/src/integration-test/kotlin/de/bixilon/minosoft/data/registries/versions/PixLyzerLoadingTest.kt
@@ -21,9 +21,8 @@ import de.bixilon.minosoft.protocol.protocol.VersionSupport
 import de.bixilon.minosoft.protocol.versions.Versions
 import de.bixilon.minosoft.test.ITUtil
 import org.testng.Assert
-import org.testng.annotations.Test
 
-@Test(groups = ["pixlyzer"], dependsOnGroups = ["version"], singleThreaded = false, threadPoolSize = 8)
+// @Test(groups = ["pixlyzer"], dependsOnGroups = ["version"], singleThreaded = false, threadPoolSize = 8)
 class PixLyzerLoadingTest {
 
     private fun VersionRegistry.test() {
diff --git a/src/integration-test/kotlin/de/bixilon/minosoft/protocol/network/connection/play/ConnectionTestUtil.kt b/src/integration-test/kotlin/de/bixilon/minosoft/protocol/network/connection/play/ConnectionTestUtil.kt
index 97d8a03e9..d3956f5ed 100644
--- a/src/integration-test/kotlin/de/bixilon/minosoft/protocol/network/connection/play/ConnectionTestUtil.kt
+++ b/src/integration-test/kotlin/de/bixilon/minosoft/protocol/network/connection/play/ConnectionTestUtil.kt
@@ -17,7 +17,7 @@ import de.bixilon.kutil.observer.DataObserver
 import de.bixilon.kutil.reflection.ReflectionUtil.forceSet
 import de.bixilon.minosoft.assets.TestAssetsManager
 import de.bixilon.minosoft.config.profile.ProfileTestUtil.createProfiles
-import de.bixilon.minosoft.data.accounts.types.offline.OfflineAccount
+import de.bixilon.minosoft.data.accounts.types.test.TestAccount
 import de.bixilon.minosoft.data.entities.entities.player.local.LocalPlayerEntity
 import de.bixilon.minosoft.data.registries.registries.Registries
 import de.bixilon.minosoft.data.world.WorldTestUtil.createWorld
@@ -36,7 +36,7 @@ object ConnectionTestUtil {
 
     fun createConnection(worldSize: Int = 0): PlayConnection {
         val connection = IT.OBJENESIS.newInstance(PlayConnection::class.java)
-        connection::account.forceSet(OfflineAccount("dummy"))
+        connection::account.forceSet(TestAccount)
         connection::version.forceSet(IT.VERSION)
         connection::registries.forceSet(Registries())
         connection.registries.parent = IT.REGISTRIES
diff --git a/src/main/java/de/bixilon/minosoft/commands/stack/CommandStackEntry.kt b/src/main/java/de/bixilon/minosoft/commands/stack/CommandStackEntry.kt
index 90238eb33..df6c42c6a 100644
--- a/src/main/java/de/bixilon/minosoft/commands/stack/CommandStackEntry.kt
+++ b/src/main/java/de/bixilon/minosoft/commands/stack/CommandStackEntry.kt
@@ -14,7 +14,7 @@
 package de.bixilon.minosoft.commands.stack
 
 import de.bixilon.minosoft.data.chat.signature.LastSeenMessageList
-import de.bixilon.minosoft.data.chat.signature.MessageChain
+import de.bixilon.minosoft.data.chat.signature.signer.MessageSigner
 import de.bixilon.minosoft.protocol.network.connection.play.PlayConnection
 import java.security.PrivateKey
 import java.time.Instant
@@ -24,7 +24,7 @@ data class CommandStackEntry(
     val data: Any?,
 ) {
 
-    fun sign(connection: PlayConnection, chain: MessageChain, key: PrivateKey, salt: Long, time: Instant): ByteArray {
-        return chain.signMessage(key, data.toString(), null, salt, connection.player.uuid, time, LastSeenMessageList(emptyArray()))
+    fun sign(connection: PlayConnection, signer: MessageSigner, key: PrivateKey, salt: Long, time: Instant): ByteArray {
+        return signer.signMessage(key, data.toString(), null, salt, connection.player.uuid, time, LastSeenMessageList(emptyArray()))
     }
 }
diff --git a/src/main/java/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner1.kt b/src/main/java/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner1.kt
index c37cd4e13..59f08df6d 100644
--- a/src/main/java/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner1.kt
+++ b/src/main/java/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner1.kt
@@ -16,6 +16,7 @@ package de.bixilon.minosoft.data.chat.signature.signer
 import com.google.common.primitives.Longs
 import de.bixilon.minosoft.data.chat.signature.LastSeenMessageList
 import de.bixilon.minosoft.data.chat.signature.signer.MessageSigningUtil.getSignatureBytes
+import de.bixilon.minosoft.data.chat.signature.signer.MessageSigningUtil.update
 import de.bixilon.minosoft.data.text.ChatComponent
 import de.bixilon.minosoft.protocol.protocol.encryption.CryptManager
 import de.bixilon.minosoft.protocol.versions.Version
@@ -28,13 +29,16 @@ class MessageSigner1(
 ) : MessageSigner {
 
     override fun signMessage(privateKey: PrivateKey, message: String, preview: ChatComponent?, salt: Long, sender: UUID, time: Instant, lastSeen: LastSeenMessageList): ByteArray {
+        return signMessage(privateKey, message, salt, sender, time)
+    }
+
+    fun signMessage(privateKey: PrivateKey, message: String, salt: Long, sender: UUID, time: Instant): ByteArray {
         val signature = CryptManager.createSignature(version)
 
         signature.initSign(privateKey)
 
         signature.update(Longs.toByteArray(salt))
-        signature.update(Longs.toByteArray(sender.mostSignificantBits))
-        signature.update(Longs.toByteArray(sender.leastSignificantBits))
+        signature.update(sender)
         signature.update(Longs.toByteArray(time.epochSecond))
         signature.update(message.getSignatureBytes())
 
diff --git a/src/main/java/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner3.kt b/src/main/java/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner3.kt
index aa02f6330..74bdbac2e 100644
--- a/src/main/java/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner3.kt
+++ b/src/main/java/de/bixilon/minosoft/data/chat/signature/signer/MessageSigner3.kt
@@ -19,7 +19,6 @@ import de.bixilon.minosoft.data.chat.signature.LastSeenMessageList
 import de.bixilon.minosoft.data.chat.signature.signer.MessageSigningUtil.update
 import de.bixilon.minosoft.data.text.ChatComponent
 import de.bixilon.minosoft.protocol.ProtocolUtil.encodeNetwork
-import de.bixilon.minosoft.protocol.network.connection.play.PlayConnection
 import de.bixilon.minosoft.protocol.protocol.encryption.CryptManager
 import de.bixilon.minosoft.protocol.versions.Version
 import java.security.PrivateKey
@@ -29,19 +28,23 @@ import java.util.concurrent.atomic.AtomicInteger
 
 class MessageSigner3(
     private val version: Version,
-    private val connection: PlayConnection,
+    private val sessionId: UUID,
 ) : MessageSigner {
     private var index = AtomicInteger()
 
     override fun signMessage(privateKey: PrivateKey, message: String, preview: ChatComponent?, salt: Long, sender: UUID, time: Instant, lastSeen: LastSeenMessageList): ByteArray {
+        return signMessage(privateKey, message, salt, sender, time, lastSeen)
+    }
+
+    fun signMessage(privateKey: PrivateKey, message: String, salt: Long, sender: UUID, time: Instant, lastSeen: LastSeenMessageList): ByteArray {
         val signature = CryptManager.createSignature(version)
 
         signature.initSign(privateKey)
 
         signature.update(Ints.toByteArray(1))
 
-        signature.update(connection.account.uuid)
-        signature.update(connection.sessionId)
+        signature.update(sender)
+        signature.update(sessionId)
 
         val index = index.getAndIncrement()
         signature.update(Ints.toByteArray(index))