Adam's solution will certainly work, but why not just use a userid wild
card i.e.,

QUIET DEL HISTARCH *@mhs-fswa.attmail.com

|>>> quiet del histarch [log in to unmask]
|>>Missing parameter - specify a target e-mail address.
|
|It doesn't like the slash. Replace them with asterisks:
|
|     QUIET DEL HISTARCH *S=M.PAUL*[log in to unmask]