I am not familiar at all with CVS. However in theory a source control application should be able to accept Flash output files. However as they are not source files, you'd not be able to integrate this with RoboHelp itself. You'd have to add them manually.
Thank you very much. I wanted to just publish the help to a folder on the CVS UNIX server. But now I think I have to go through a manual check in procedure.
Why not just give it a try? If you've got the right permissions, it should just get copied up to the server; if it can't do it, RH or your CVS server will let you know - no harm done.