cvs update to branch with -f option

[Anne-Marie_Buibish]

I am working in an environment where several new features are being
developed in different branches for the same repository.  We are using
WinCVS and our team is about 30 developers working in mini-teams of 1 or
more.  Our application is over 100K SLOC of java.  We are having challenges
in our multi-team environment.  In general, we are trying to handle our
build and concurrent development issues.

Each branch has a few developers working on a handful of files.  A
developer working in a branch performs a checkout for the branch with the
-f option, giving him an entire repository to work from consisting of the
branched files, and the remainder of the repository from the main trunk.
This developer then commits his changes to the branch for the other
developers working in his branch.  The other developers working in that
branch then perform an update to the branch with the -f option, again
giving them the files committed by other developers in that branch and the
remainder of the repository from the main trunk.

This method works well for us, except when the -f option is used, I would
like to get the non-matching files from a tag, rather than from the main
trunk (eg HEAD).

This would allow other developers to commit to the trunk as needed, without
affecting the developers working in a branch.  At a given point in time, a
new tag would be created (treated as a "build snapshot") and made available
to developers for updating at their convenience.

Does anyone know if and how this can be done?  Maybe another approach?  How
are other teams meeting some of these same needs?

Thank you!