Everything was working fine until we activated the Firewall. Now Limewire doesn't work even with 6346 open. Are there any other ports that Limewire uses for incoming traffic?

Wierd thing is that Limewire doesn't work on our Macs but it works on the PCs on the same network. Same thing with IRC, works on a PC but not on a mac. I'd think it was something wrong with the mac, but we have about 20 macs here and acquisition doesn't work on any of them. And, when we turn off the firewall, everything works OK. There's gotta be something that the firewall is blocking besides 6346.

any ideas?