Installation to existing XEN system?

I have an existing debian 5 xen host, currently holding around a dozen xen virtual machines (all debian also). I'd love to install cloudmin GPL on it but all the guides seem to suggest needing a clean base system. I'd like to avoid the hassle of rebuilding the server at this point, so I'm curious if there is any reason that I can just add the cloudmin repos to apt and install that way. Will Cloudmin be able to handle my already existing virtual machines?

Cheers

UndisclosedP