When passing over a network address translater, IRC has been known to sometimes cause problems. This is because for DCC to work, a connection must be made back to the client, just as FTP works.
Some address translators don't handle this properly and it could cause the connection not to work or eve cause the hardware to crash.
If that's the case, he might try upgrading the firmware, but on those Marconi modems, that usually only makes the problem worse.
What I suggested is that he remove his username and password from the modem, meaning that it not function as a PPPoE client. Instead, he should run the PPPoE client on one of his machines, as you do with the USB version of the modem. If he uses a USB modem, he needs to fix the software on his PC.
The best solution, of course, is a real ethernet bridge, like a D-Link DSL300G, and a real PPPoE client running on a real NAT (a FreeBSD machine comes to mind.)
Willie Viljoen
Web Developer
Adaptive Web Development
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