"+" bug in mac_key?

[meepbear *]

>Now, I appreciate that this is a bit of a weird bug, but I thought I'd 
>throw it into the mix and see if it meant anything to anyone.

Version 1.2.7 doesn't appear to do any padding in case the high bit is set 
which will result in mismatched calculated mac keys.
Another thing I noticed is that your generated keys have 160 bit entropy 
while the default mod is (rounded up) a 1024 bit number.