[libvirt] How to solve this problem---libvirtError: this function is not supported by the connection driver: virNWFilterDefineXML

Dear all: I am trying to deploy openstack on xen hypervisor.Since XenSever or XCP is not available on our customized virtulization platform. We decide to use libvirt on xen as a middleware operating the xen hypervisor. But when I try to boot a instance , xen failed to response and I find the error in my nova.log as follows: 2012-08-24 09:17:25 ERROR nova.compute.manager [req-4b60e9a9-680c-457b-bf93-b71fb6230245 562096602c5e41748dd568d5db0f7553 6bd4a2580bcd4bef890d7ba4da82e925] [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] Instance failed to spawn 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] Traceback (most recent call last): 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] File "/usr/lib/python2.6/site-packages/nova-2012.1-py2.6.egg/nova/compute/manager.py", line 592, in _spawn 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] self._legacy_nw_info(network_info), block_device_info) 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] File "/usr/lib/python2.6/site-packages/nova-2012.1-py2.6.egg/nova/exception.py", line 114, in wrapped 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] return f(*args, **kw) 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] File "/usr/lib/python2.6/site-packages/nova-2012.1-py2.6.egg/nova/virt/libvirt/connection.py", line 899, in spawn 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] self.firewall_driver.setup_basic_filtering(instance, network_info) 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] File "/usr/lib/python2.6/site-packages/nova-2012.1-py2.6.egg/nova/virt/libvirt/firewall.py", line 231, in setup_basic_filtering 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] self.nwfilter.setup_basic_filtering(instance, network_info) 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] File "/usr/lib/python2.6/site-packages/nova-2012.1-py2.6.egg/nova/virt/libvirt/firewall.py", line 102, in setup_basic_filtering 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] self._ensure_static_filters() 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] File "/usr/lib/python2.6/site-packages/nova-2012.1-py2.6.egg/nova/virt/libvirt/firewall.py", line 130, in _ensure_static_filters 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] 'allow-dhcp-server'])) 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] File "/usr/lib/python2.6/site-packages/nova-2012.1-py2.6.egg/nova/virt/libvirt/firewall.py", line 150, in _define_filter 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] tpool.execute(self._conn.nwfilterDefineXML, xml) 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] File "/usr/lib/python2.6/site-packages/eventlet/tpool.py", line 76, in tworker 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] rv = meth(*args,**kwargs) 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] File "/usr/lib64/python2.6/site-packages/libvirt.py", line 2628, in nwfilterDefineXML 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] if ret is None:raise libvirtError('virNWFilterDefineXML() failed', conn=self) 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] libvirtError: this function is not supported by the connection driver: virNWFilterDefineXML 2012-08-24 09:17:25 TRACE nova.compute.manager [instance: 3645be21-9b5b-4718-9c9f-f6ba3588f7b4] It seems that libvirt doesn't support virNWFilterDefineXML on xen,Is there any good solutions? Or how much work should be done to add this function to libvirt? I would take it into consideration seriously if I could fix this problem