too few colours ...

I've just installed Ubuntu 6.06 on my iMac, and from there installed MoL
0.9.70-20ubuntu.

It "just works", and is excellent fun! I'm on an iMac 17' lcd with
geforce4 440.

However, I'd like to run OSX full-screen, so I ran molvconfig -- the
only mode that it finds is "current" (1440x900) at 8 bits ... all the
other modes are "bad", and when mol runs I get only 256 colours, with
extreme stippling on some areas rendering them unuseable.

What should I do to improve the video modes?

-jim