RedHat 7.2 Freezing up

["Matt Sales" <sales sealsco com>]

Hello,
I'm having a problem with one of my servers continually crashing...  The
system will go to sleep and not wake up.  When I review the logs, the last
entry is a seemingly random "[date:time] [servername] network: Shutting down
interface eth0: succeeded".  I have no idea why the machine would suddenly
freeze and shut down the network interface...?  It ensures I can't get to it
at all, and that I have to pull the plug to restart the machine.  I
originally upgraded the machine in question (Compaq Presario/431 MHz
Celeron) from RH6.0 (where it was working flawlessly) to RH7.2.  Immediately
after the "upgrade," it was doing something similar (without the log entry)
and I was advised to change the ext3 partitions back to ext2.  It has worked
fine for about a month since, and now this...  Has anyone else been having
similar problems?  Any help would be greatly appreciated.

Thanks,
Matt