Are you using seperate interfaces or VLAN's? If you are connected to the same BSR with the cable modem's it's not going to like the MAC address most likely. Also, do you have a switch connected the the cable modems, then the switch connected to the firewall? I have found that when using the same BSR is breaks the second cable modem for some reason.
-- Curtis LaMasters http://www.curtis-lamasters.com http://www.builtnetworks.com
