non-standard CFB (Re: Lutz formal spec / ROT-13 persists)

Werner Koch <wk(_at_)isil(_dot_)d(_dot_)shuttle(_dot_)de> writes:
> By the way, is is really required that PGP's strange CFB mode is
> required for other ciphers that IDEA?
I argued against earlier on list, and argued for the non-standard CFB
to be depracated for all ciphers.  However I think pgp5.x already is
deployed with non-standard CFB for CAST (and I presume 3DES also).

Adam