Yes NAT does appear to be more evil,
as an ex-server admin I hated dhcp as well.
Nat fix:
get tor
http://www.freehaven.net/tor/
point your irc, aim etc. through there using
socks5 (or socks 4 with privoxy) works for me
on my college net.
or find a free proxy server somewhere and use that instead.
www.samair.ru/proxy has a list
:)