I recently started using BATV to filter out unwanted bounce email spam.  I configured the feature as per instructions, including seed value, email policy, and group policy.  The validation works, and filters out the spam bounces.  Remaining problem is that SMG does not remove the prvs or validation tag from legitmate returned failed emails, or NDRs, which means that those NDRs are not sent to the sender, although the postmaster email account receives a copy.  Without the removal of the prvs, SMG forwards the NDR to our Exchange server using the Return to address that includes the private signature, such as prvs=xxxxxxx=sender@domain.com, and Exchange cannot deliver it, for obvious reasons.   

I am using the latest version of SMG, as a virtual appliance.  Any suggestions would be greatly appreciated.

Jim