+Single messages (as opposed to ranges) may also be selected by
+substituting `=' for `:', as in \*(lqname=n\*(rq. This will reduce
+the selection from being a range of up to `n' messages, to being a
+selection of just the `n'th message. So while \*(lqseq:5\*(rq
+selects the first 5 messages of seqence `seq', \*(lqseq=5\*(rq
+selects just the 5th message of the sequence. It is
+an error if the requested message does not exist (i.e., there aren't
+at least `n' messages in the sequence).
+.PP