BM 3.8, NW 6.5 sp4
Pretty regularly we get the following error message from 1 website:

Your request is not being processed

ERROR: Your firewall is not properly transmitting the original header for
this request.
IP: (public IP of my BM server)

This is only happening on 1 site, it happens to be our website. I spoke
to their support and they said it had to do with the host headers not
coming through to them correctly. As this is a hosting site, they return
the correct virtual site based on the host header. I'm pretty sure this
is proxy related because I can unload and reload proxy and it clears
up....until the next time.