[libvirt] Start external programm on network-setup

Hy, im using libvirt-bin on debian and configured the network of libvirt to be a standalone bridge. Is there a possibility to run a program after the bridge has successfully and completly set up by libvirtd? I would like to restart shorewall (a firewall) when the bridge is set up to activate MASQ and DNAT and other policies which I need. I would also like to start my own configured dnsmasq when the interface is up (can't start it realier because it has to bind to the interface). I hope thats the right place to ask such a question, if not, please direct me. Thanks for the help -- Dominik mailto: dominik(a)dbruhn.de