Solaris on Xen on Acer 9524

Hello everyone,

today I tried to install Solaris on XEN on my Acer Notebook.

I installed OpenSolaris Build 44 which runs fine. Then I installed the required 
downloads and edited /boot/grub/menu.lst

Then I tried to boot into XEN, but it crashes with the message

Panic on CPU 0
IOAPI[1] unable to change apic_id

So I added noapic to the xen command line. Now XEN boots but Solaris falls into 
kmdb because it can't get the apic information.

Any hints how to get that running ?

Sincerely
Bernhard