System freeze on dial-up

[mph]

I've installed PC-BSD 1.0-rc2 on a PIII 500MHz machine, 256MB RAM, onboard Matrox video and I'm assuming an Intel chipset. The install went ok and the 2 updates installed succesfully via my adsl connection.

However, the person I built the machine for is using dial-up internet. It dials up ok and happily goes about browsing the web. But, after about 15-30mins of being connected the whole machine freezes. I can't drop back to a console screen, nothing. Then after about 30-60sec of being frozen, the machine reboots.

Now this machine has been happily running Win2k with the same dial-up modem for quite sometime, so I'm assuming it's not hardware. The machine also ran fine at my place for a couple of days without a hitch.

Can anyone offer any insite to this issue?

Cheers,
Matt.