[CentOS] openvpn server: one client works; one fails.

I installed an openvpn-2.0.9 server on my new CentOS 5.4 box from
using the same parameters I used on a Fedora box I retired.

Now I have a dual boot laptop that has WinXP and Fedora FC8.  Both of
these partitions have openvpn clients installed that have worked well in
the past.

After adjusting these for new IP addresses, I find:

   WinXP:  connects and contacts boxes on the same
           LAN as the server.

   FC8     appears to connect but will not contact
           anything.

Since I have nested routers, I was able to disconnect from the real WAN,
and use an emulated WAN.  I then shut off iptables on both Linux boxes. 
The behavior was not altered.

BTW, I use TAP rather than TUN.

I have run out of ideas.  Suggestions would be most welcome.

Thanks,
Mike.