No subject

mail [mail at sub.ourserver.net]; on behalf of; John Doe via RT
[requests at ourdomain.com]

The only problem is, some recipients' ISPs do not like the first part of the
from field (mail at sub.ourserver.net). It never arrives there at all.

My question is this: Is there a way to configure RT so the From field
becomes only this instead:

John Doe via RT [requests at ourdomain.com]


Thanks for any help you guys might offer!

John DeBerry