groups via NIS. -> different UIDs on server and client. an easy way out?

Since I switched to gentoo linux I have had several problems on my NIS
client.
I have traced the problem to not being in the correct groups. (gentoo has
very specific group requirements).

please see http://forums.gentoo.org/viewtopic.php?p=1642428 for my original
call for help.

my problem now is:

the MINGID variable in /var/yp/Makefile on the NIS server. ATM it's set to
500 so only nobody and nogroup are included in the nis map.

I can change MINGID to 10 (to include wheel, audio, games for eg.) but the
GID for many groups are different on my client as opposed to my server.

please tell me there is an easy way round this...

thank you

Aron