Did you just purchase or upgraded the PIX IOS? If so, then you probably have one of the 7.XX version PIX IOS which is buggy and unstable. I used to work for MSSP companies and we would run into these situation where the PIX would reboot out of the bl...
You would need to debug the access-list:1) Disable fast switching on the interfaces involved. You only see the first packet if fast switching is not disabled. config interfaceno ip route-cache2) Use the "terminal monitor" command in enable mode in or...