-If defined and set to 1, then the
-.B whatnow
-program will automatically
-invoke the buildmimeproc (discussed below) to process each message as a MIME
-composition draft before it is sent.
-(profile, no default)
+The (pseudo) header in draft messages, that contains files to be attached
+to the message on sending.
+If you like to type a lot, name it `X-MH-Attachment'.
+(profile, default: `Attach')