A while ago I found a bug in ObHack 006b which I decided wasn’t worth the time to fix.
Well, Fritz has fixed this bug. I have a patch at the following location:
http://samiam.org/slump/secret-spoiler.patch
Note that this patches cleanly against 006b, but does not patch cleanly against Fritz’s ObHack 006.4 release. I am sure Frtiz’s next ObHack release will have this bug fixed.