I got problems running sb_mboxtrain.py (AttributeError: 'NoneType' object has no attribute 'learn') which I solved by upgrading spambayes to 1.1 alpha2. This version should be imho added into portage (based on ebuild in bug 96987 that has been marked imho wrong as duplicate of 79917).
i'll have a look (i didn't mark the other one as duplicate .. i didn't even seen it ;))
Re-assigning to herd wrt Bug 155664.
Fixed in CVS. Thanks!