Check if your kernel was built with:

CONFIG_XEN_BLKDEV_FRONTEND=m
CONFIG_XEN_NETDEV_FRONTEND=m

Add modules to initrd (in DomU)

echo "xen-blkfront" >> /etc/initramfs-tools/modules
echo "xen-netfront" >> /etc/initramfs-tools/modules

Update initrd (in DomU)

update-initramfs -u -k all

diff -urNad centerim-4.22.9~/src/icqcontacts.cc centerim-4.22.9/src/icqcontacts.cc
--- centerim-4.22.9~/src/icqcontacts.cc 2010-01-12 09:55:38.000000000 +0200
+++ centerim-4.22.9/src/icqcontacts.cc  2010-11-15 02:03:21.000000000 +0200
@@ -374,5 +374,5 @@

     }

-    c->setgroupid(gid);
+    c->setgroupid(gid, false);
 }