diff --git a/src/main/scala/li/cil/oc/server/driver/Registry.scala b/src/main/scala/li/cil/oc/server/driver/Registry.scala
index 31bfaefe9..53fa7f89a 100644
--- a/src/main/scala/li/cil/oc/server/driver/Registry.scala
+++ b/src/main/scala/li/cil/oc/server/driver/Registry.scala
@@ -102,6 +102,7 @@ private[oc] object Registry extends api.detail.DriverAPI {
       case arg: Array[_] => convertList(arg, arg.zipWithIndex.iterator, memo)
       case arg: Product => convertList(arg, arg.productIterator.zipWithIndex, memo)
       case arg: Seq[_] => convertList(arg, arg.zipWithIndex.iterator, memo)
+      case arg: java.lang.Iterable[_] => convertList(arg, arg.zipWithIndex.iterator, memo)
 
       case arg: Map[_, _] => convertMap(arg, arg, memo)
       case arg: mutable.Map[_, _] => convertMap(arg, arg.toMap, memo)
@@ -117,6 +118,11 @@ private[oc] object Registry extends api.detail.DriverAPI {
           memo += arg -> null
           null
         }
+        else if (converted.size == 1 && converted.containsKey("oc:flatten")) {
+          val value = converted.get("oc:flatten")
+          memo += arg -> value // Update memoization map.
+          value
+        }
         else {
           // This is a little nasty but necessary because we need to keep the
           // 'converted' value up-to-date for any reference created to it in