IOS 123-5a 3620 CBAC SMTP issue

[Aaron D]

I recently tested a 123-5a image. On reboot, my external smtp clients would fail on pop3. On troubleshooting, I found the access-list was fine. When, though, I would apply the firewall even with a wide open access-list the external smtp clients would fail. Anyone know about this issue? I checked the release notes below and found nothing. Its on a 3620 16Flash 64mb ram. Any help appreciated. I had to roll back to a 12.2 T train and it works fine.

http://www.cisco.com/en/US/partner/products/sw/iosswrel/ps5187/prod_release_note09186a008017d261.html#1672043

[gfullage · Accepted solution]

Probably CSCec78231 (http://www.cisco.com/cgi-bin/Support/Bugtool/onebug.pl?bugid=CSCec78231&Submit=Search), this is a fairly major IOSFW bug. Basically TCP sessions initiated on the outside don't work cause the SYN/ACK reply coming from the inside host gets dropped.