Windows Server 2012 RDS CALS on Windows Server 2008 R2 Licensing Server

Hi,

at the moment we are installing the first couple of Windows Server 2012 in our infrastructure.

Some of them have installed RDS.

Now we are wondering whether it is possible to use our existing Windows Server 2008 R2 licensing server for serving the licenses we have (yes we to have new Windows Server 2012 RDS CALS) or whether we have to install a new host based on Windows Server 2012.

We tried to add the new license to the 2008 R2 licensing server, but it is not possible. The licensing manager's error message: "The license code contains invalid characters or not enough characters."

Is there any other way?

Thanks and regards
Matthias