diff --git a/docs/rh-log.txt b/docs/rh-log.txt
index 57e9c8ce4..e77a75e8c 100644
--- a/docs/rh-log.txt
+++ b/docs/rh-log.txt
@@ -1,3 +1,6 @@
+August 27, 2006 (Changes by Graf Zahl)
+- fixed: callstatechain didn`t check for NULL code pointers
+
 August 25, 2006
 - Fixed: Multiple-choice sound sequences could not be assigned IDs for use
   with polyobjects and the sound sequence selector things.
diff --git a/src/thingdef_codeptr.cpp b/src/thingdef_codeptr.cpp
index cb24d2236..36fbbdca3 100644
--- a/src/thingdef_codeptr.cpp
+++ b/src/thingdef_codeptr.cpp
@@ -109,12 +109,15 @@ bool ACustomInventory::CallStateChain (AActor *actor, FState * State)
 	while (State != NULL)
 	{
 		// Assume success. The code pointer will set this to false if necessary
-		StateCall.Result = true;	
 		CallingState = StateCall.State = State;
-		State->GetAction() (actor);
+		if (State->GetAction() != NULL) 
+		{
+			StateCall.Result = true;	
+			State->GetAction() (actor);
+			// collect all the results. Even one successful call signifies overall success.
+			result |= StateCall.Result;
+		}
 
-		// collect all the results. Even one successful call signifies overall success.
-		result |= StateCall.Result;
 
 		// Since there are no delays it is a good idea to check for infinite loops here!
 		counter++;