--- a/signs.h	Sun Jul 17 20:09:02 2005 +0000
+++ b/signs.h	Sun Jul 17 20:14:58 2005 +0000
@@ -58,6 +58,6 @@
 void PlaceProc_Sign(TileIndex tile);
 
 /* misc.c */
-void ShowRenameSignWindow(SignStruct *ss);
+void ShowRenameSignWindow(const SignStruct *ss);
 
 #endif /* SIGNS_H */