+The
+.B \-messageid
+switch selects the style used for the part appearing after the @
+in \*(lqMessage\-ID:\*(rq, \*(lqResent\-Message\-ID:\*(rq, and
+\*(lqContent\-ID:\*(rq header fields. The two acceptable options are
+.B localname
+(which is the default),
+and
+.BR random .
+With
+.BR localname ,
+the local hostname is used. With
+.BR random ,
+a random sequence of characters is used instead. Note that the
+.B \-msgid
+switch must be enabled for this switch to have any effect.
+.PP