Virtual Center uses a Flexnet licensing server. You can head over to http://www.macrovision.com/products/licensing/flexnet_manager.htm and do some reading. They support a limited number of distros but, if this is required and you don't mind spending some $ to have your licensing server on linux, you should be able to put one up and point VirtualCenter at it.
Not sure why your licensing server, if you don;t have one already, needs to be on Linux though.
