We've been getting sporadic return errors from a subscriber.  I figured odds are
that someone here has run into this particular one before.  Thanks for any help
- stats are below.

Audrey, Fibrom-L

Subject: Returned mail: Error During Delivery

------ Here is your List of Failed Recipients ------
<[log in to unmask]>

Destination mail server returned error code 453.

-------- Here Is Your Returned Mail --------
Received: FROM cherry.ease.lsoft.com BY virscan.xxx.net