[PATCH] fix to mc-verify-signature

[<ne...@us...>]

(see also: https://sourceforge.net/tracker/index.php?func=detail&aid=1093072&group_id=397&atid=300397 )

mc-verify-signature has a comment:

; We can't find a message signed in the default scheme.
; Step through all the schemes we know, trying to identify
; the applicable one by examining headers.

I think this is a wrong approach. If the "header" doesnt exist in the
current scheme, then we move to a scheme we don't have loaded. For
instance, if I do (mc-setversion "gpg") and then C-c / v, mailcrypt
craps out with "Symbol's value as variable is void:
mc-pgp50-fetch-key". PGP50?? I'm trying to use GPG!!  Additionally I
get this same error when I try to verify a signature on an email that
is not signed! So, while we're trying to loop through schemes, we're
not doing it correctly.

I think we shouldn't be trying to second guess the user. If we dont
know know the user is trying to acomplish, then we should throw and
error and say we're confused.

Attached is a patch against the current CVS (12/29/04) that removes
the loop across the schemes in mc-toplevel.el