Organizing 2 project which share code

[Giuseppe Milicia]

Hi everyone,

I have to set up CVS to handle 2 projects which share lots of code. The
shared code is evolving, and I want people working on either project to be
able to modify the common code.
Nevertheless people on different projects should not be aware of project
specific code.

So when you do an update/commit on common code everyone gets is.
But when you do a checkout you do not get the project specific code...

What would be the best way to organize this?? Actually is it possible at
all?

Thank you,

-- Giuseppe