Hi, unfortunately, the Xen images are "images", i.e. a tar'ed filesystem. They cannot be imported into the XenServer. Xen (the open sourced technology underlying XenServer) and XenServer seem to be very different products when it comes to migrating VMs. Here is a page that explains the difference between the XenServer (5.5) XVA and the OVF format:

http://support.citrix.com/article/CTX121652

There seem to be some tools to convert between XenServer, OVF and VMWare:

http://www.xen.org/products/cloud_projects.html

http://support.citrix.com/article/CTX116603

I can try to do this myself - but wondered if you had plans to support XenServer so I could save myself some trouble.

Thanks!