Yes the new version of RoboCopy can check/purge files... but you could also have it output a list of files then parse it and feed it to a zip script.

Here is a zip script post.
http://www.kixtart.org/ubbthreads/showflat.php?Cat=0&Number=60855

And this post uses 7Zip to archive
http://www.kixtart.org/ubbthreads/showflat.php?Cat=0&Board=UBB2&Number=135181
 
Good luck, let us know how it goes.