--- a/src/strings.cpp	Thu Aug 02 21:02:57 2007 +0000
+++ b/src/strings.cpp	Thu Aug 02 21:05:54 2007 +0000
@@ -824,7 +824,7 @@
 				const Town* t = GetTown(GetInt32(&argv));
 				int64 temp[1];
 
-				assert(IsValidTown(t));
+				assert(t->IsValid());
 
 				temp[0] = t->townnameparts;
 				uint32 grfid = t->townnamegrfid;