I'm not 100% positive, but I've heard that some ISP's block port 28960 outgoing, so you can't host a COD 4 server, but umm, try opening 28960 on both the TCP and UDP protocols, not just UDP.
Also, open port 53 to your PC, open your firewall on your PC, or better yet turn it off, and when hosting your server, make sure you type
+set dedicated 2 +set sv_punkbuster 1 +exec mp_server.cfg +map_rotate
You do know how to host a server don't you?
Anyways let me know how it goes.
I do not know much about the cansol commands all i do is select start your own server from menu +dedicated to internet and start.. nothing else.