I am having a problem with pop3/smtp and nat...

I have nat set both dynamically as well as staticly...if I have a nat'ed
ip (private address to public address) pop and smtp work fine...but if it
is a regular dhcp machine that uses the dynamic nat...Pop3/smtp times
out...and I cannot telnet to 110...

Any ideas....

I have unloaded filtsrv.nlm and I seem to still have the issue...