Type: string
Default: "pgp-md5"
This variable contains the default message integrity check algorithm. Valid values are ``pgp-md5'', ``pgp-sha1'', and ``pgp-rmd160''. If you select a signing key using the sign as option on the compose menu, mutt will automagically figure out the correct value to insert here, but it does not know about the user's default key.
So if you are using an RSA key for signing, set this variable to ``pgp-md5'', if you use a PGP 5 DSS key for signing, say ``pgp-sha1'' here. The value of this variable will show up in the micalg parameter of MIME headers when creating RFC 2015 signatures.