ps -ef | grep xen  (after the "crash" happened) 

root        11     9  0 11:28 ?        00:00:00 [xenwatch]
root        12     9  0 11:28 ?        00:00:00 [xenbus]
root      3039     1  0 11:28 ?        00:00:00 xenstored --pid-file /var/run/xenstore.pid
root      3044     1  0 11:28 ?        00:00:00 python /usr/sbin/xend start
root      3045  3044  0 11:28 ?        00:00:00 python /usr/sbin/xend start
root      3047     1  0 11:28 ?        00:00:00 xenconsoled
root      3280  3045  3 11:30 ?        00:00:11 /usr/lib/xen/bin/qemu-dm -d 1 -domain-name W2k3_szpn0001 -k de -vnc 0.0.0.0:0 -vncunused -vcpus 2 -boot dc -localtime -serial pty -acpi -usb -usbdevice tablet -net nic,vlan=1,macaddr=00:16:3e:00:00:11,model=rtl8139 -net tap,vlan=1,bridge=xenbr0 -M xenfv