[newbie] Reverse DNS?

[holiday]

I've been trying to transfer mail with fetchmail but having a recurring 
problem. I connect with kppp, telling it to use the remote DNS 
servers, and then launch a konsole window to run fetchmail. 
Fetchmail connects to the servers fine, but appears to try to 
perform some sort of reverse DNS check on each mail, flushing 
each one from the local cache. I presume it's trying to use a local 
nameserver.

Can anyone help? This problem is forcing me to continue using 
windoze for my e-mail.

Cheers. James.