Mapping between windows and unix groups samba 3.0 feature

[Tait Shrum]

I see on the samba 3.0 roadmap that mapping between windows, and unix 
groups code is written, but not documented.
What does this add to samba?  Does this deal with windows domain groups?
The feature we are desperately seeking from samba is the ability to map 
shares based on group membership.
Implementing a pre-exec script for this seems overkill.  One thing I 
have noticed is samba's ability to map based on group membership.
We can assign someone to be a member of  group student, then assign a 
share to allow anyone from group student to access, and it works great.
Can we take advantage of this feature somehow?

Does samba 3.0 do something different, to give us the ability to do 
things based on group membership based on login script?
We are really trying to duplicate Novell's ifmember functionality.
Does this mapping between windows, and unix groups allow the 
ifmember.exe to work on the windows client side?
(the one that would normally run for windows/nt networks/?)

Thanks,
Tait Shrum
District Network Administrator
Bryant Public Schools
Bryant, AR