Virtualisation of linux/solaris

Hello,

I need to build a server with both solaris and linux guest VM using full virt on x64.
The guest os are solaris 10 (not opensolaris) and linux RedHat (Centos) and Suse.
I really cant make run a solaris 10 domU on Linux (hang after grub loader ..... ) Dom0 neither on opensolaris 11 xvm (hang and run very very slow).
Virtualbox is not an option for me and I tried on new esxi product and it works fine but I wish to stay on opensource hypervisor.

Anybody was able to run Solaris (again not opensolaris) as domU on xen ?
Any other open source solution than can help me ?

thanks,