I seem to have problems with RH 6.2 on my Belgian cable ISP "Telenet".

I have several 6.1 & 6.2 boxes running as MASQ boxes.

Now, all the 6.2 boxes seem to suffer from 
Aug 25 01:21:21 dhcp-213-224-38-76 pumpd[273]: failed to renew lease for 
device
(actually all do it at the same time)

The 6.1 boxes seem to work perfectly and get their DHCP leases. 

Now I don't doubt it that there was a network problem, but RH 6.1's pump 
seems to be far more robust than theone in 6.2.
The average pump-uptime of RH6.1 is 3 months against one week for 6.2.

Is there a solution to this problem? Or should I upgrade/downgrade pump (I 
already tried to use the RPM from the RH bita release...but the RPM seems 
to be in a different format).