Index: src/script/squirrel.cpp
===================================================================
--- src/script/squirrel.cpp	(revision 18033)
+++ src/script/squirrel.cpp	(working copy)
@@ -229,7 +229,7 @@
 	if (ret != NULL) sq_getstackobj(vm, -1, ret);
 	/* Reset the top, but don't do so for the AI main function, as we need
 	 *  a correct stack when resuming. */
-	if (suspend == -1) sq_settop(this->vm, top);
+	if (suspend == -1 || !this->IsSuspended()) sq_settop(this->vm, top);
 	/* Restore the return-value location. */
 	this->vm->_suspended_target = last_target;