using linux OS user group for htaccess user group

[sank]

I have a secure section of a multifunction server that I want
accessible to the people that have accounts on the server (and are in
a particular user group).

Besides the hassle of trying to duplicate the user list in .htpasswd,
it would be a real maintenence nightmare to maintain the two lists of
users and passwords, with users changing passwords and people leaving
and joining the group and whatnot.

There must be a simple way to link http auth users to user account
groups on the linux box?

Thanks!