[CentOS] Nvidia forcedeth stops working

I just installed CentOS 6.3 on a Tyan motherboard and the NIC stopped 
talking after about 2 days of operation. It's connected to a Cisco 2950 
switch. /var/log/messages has this in it:

nv_stop_tx: TransmitterStatus remained busy

I simply did an "ifdown eth0" and "ifup eth0" to bring it back to life 
again.

I think I have this issue:

<http://www.centos.org/modules/newbb/viewtopic.php?topic_id=18183>

Is this a regression? Any suggestions on what I can try here?