RDS License Server with 2008 and 2012 hosts

I have a domain with two 2008 R2 servers, one being the licensing host and one being the license server.  We want to add a 2012 server as well.  Will the 2008 RDS licenses cover the 2012 server or do we need to add 2012 RDS licenses?  If we do, which I expect to be the correct answer, can the current 2008 license server handle those at the same time as the current 2008 licensing requirements which won't change.