I had the same problem. I am told that we do not have an authoritative server 
for network 10 with out internal network. My solution was to include all router 
ip addresses in my /etc/hosts file.
Gil Irizarry

>>> Massimo Carnevali <Massimo.Carnevali AT COMUNE.BOLOGNA DOT IT> 04/30 8:45 
>>> AM >>>
I too noticed this problem. It seems that for a small perdiod of days
trying to resolve
internal addresses (like 10.*.*.*) on the external world gave that answer.
Check your DNS inverse ip resolution, may be it is asking outside what it
should
keep inside.
Hope this helps.
Massimo Carnevali - IBM Global Services -Italy