Could someone unsubscribe the non-existant user

>     ----- Transcript of session follows -----
>  ... while talking to alisa1.lockheed.com.:
>  >>> RCPT To:<ERNSTE@alisa1.lockheed.com>
>  <<< 550 No such AlisaMail user here: Invalid address - ERNSTE
>  550 <ERNSTE@ALISA1.LOCKHEED.COM>... User unknown

I'm sure everyone that posts to the list gets a bounce from this guy.

Alternatively, would anyone mind if I unsubscribe this guy?

Roger