1.4 Where did the ip_masq_vdolive / ip_masq_quake / ... modules go? Some of them are not required, and some haven't been ported to netfilter yet. Netfilter does full connection tracking even for UDP, and has a policy of trying to disturb the packets at little as possible, so sometimes things `just work'.
So, you may be in luck, but it's not all there yet. YMMV.
HINT: Google is your friend...
HINT: Read the FAQ...