Long about 08:21 AM 2/23/2011, Eric Johnson sent the following:

>1 02/22 02/22 [log in to unmask]
>                 Last error: 5.1.1 550 5.1.1
> <[log in to unmask]>: Recipient
>                             address rejected: User unknown in relay recipient
>                             table
>
>I had 20 errors last night of this type. Same domain but different
>addresses and
>the addresses seem to be in hex.

Looks like spam backscatter.

-- DCP