diff --git a/Source/p_setup.c b/Source/p_setup.c
index 39981fba..b8145ed0 100644
--- a/Source/p_setup.c
+++ b/Source/p_setup.c
@@ -292,7 +292,8 @@ void P_LoadNodes (int lump)
         char fmt[5];
         memcpy(fmt, data, 4);
         fmt[4] = '\0';
-        I_Error("Unsupported nodes format: %s\n", fmt);
+        I_Error("Unsupported nodes format for %s: %s\n",
+                lumpinfo[lump-ML_NODES].name, fmt);
       }
   }