* Bug

mml-smime-openssl-sign always takes the cdar of smime-keys, resulting in
keyfile parameter of the #secure tag being ignored.  Hence, only the
first entry of smime-keys is used, regardless of the mail contents or
sender address.

* Fix

The relevant information (returned from mml-smime-openssl-sign-query) is
already in the cont alist passed to mml-smime-openssl-sign, just use
that instead.