8139too driver has problem?

[SHIBUYA Katsutoshi]

Hi.  I'm using RTL8139 based NIC and having a trouble.
It works just fine at day-time but it frequentry stops working at 
midnight (23:00-6:00 varing day by day).
When it occurs, all communications via eth0 device don't work; ping 
from the host to another host, ping from another host to the host, ssh 
connections, smtp connections etc.
When I unplug the ethernet RJ45 connector once and plug it again, it 
becomes work well again.
Once I tried "/sbin/ifdown eth0" then "/sbin/ifup eth0", but the device 
was still stalled.
Rebooting the Linux the connection became OK.
Watching the LED on the ethernet HUB, the link looks like OK and has 
signals.
No messages are left on /var/log/messages, /var/log/secure, 
/var/log/cron around that moment.
Finally I created a small script which checks the ping result to the 
neighbor host and if failed reboot the Fedora. (since I am tired to be 
a sentry all the night.)

I found a document mentioning about such problem;
http://linux24.sourceforge.net
Here they say "RTL 8139 cards sometimes stop responding. Both drivers 
don't handle this quite good enough yet."
but in the "Fixed" section...

How do you think about this problem?  My host has been cracked every 
night?  Or 8139too driver still has problem?
How can I fight against it?
Any suggestions appreciated.

#I'm sorry with my poor english...
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SHIBUYA Katsutoshi (shibuya at bu-denken.co.jp)