manual vconfig needed on nova-network startup

If I try to start nova-network (vlan-manager) I get the error that vlan#100 can't be added to unnamed interface (see log output). If I manually do 'vconfig add br100 100' network starts fine.

2011-07-15 14:54:27,370 DEBUG nova.utils [-] Running cmd (subprocess): ip link show dev vlan100 from (pid=28536) execute /usr/lib/pymodules/python2.7/nova/utils.py:143
2011-07-15 14:54:27,374 DEBUG nova.utils [-] Result was 255 from (pid=28536) execute /usr/lib/pymodules/python2.7/nova/utils.py:161
2011-07-15 14:54:27,375 DEBUG nova.linux_net [-] Starting VLAN inteface vlan100 from (pid=28536) ensure_vlan /usr/lib/pymodules/python2.7/nova/network/linux_net.py:465
2011-07-15 14:54:27,375 DEBUG nova.utils [-] Running cmd (subprocess): sudo vconfig set_name_type VLAN_PLUS_VID_NO_PAD from (pid=28536) execute /usr/lib/pymodules/python2.7/nova/utils.py:143
2011-07-15 14:54:27,383 DEBUG nova.utils [-] Running cmd (subprocess): sudo vconfig add None 100 from (pid=28536) execute /usr/lib/pymodules/python2.7/nova/utils.py:143
2011-07-15 14:54:27,392 DEBUG nova.utils [-] Result was 3 from (pid=28536) execute /usr/lib/pymodules/python2.7/nova/utils.py:161
2011-07-15 14:54:27,392 CRITICAL nova [-] Unexpected error while running command.
Command: sudo vconfig add None 100
Exit code: 3
Stdout: ''
Stderr: 'ERROR: trying to add VLAN #100 to IF -:None:- error: No such device\n'
(nova): TRACE: Traceback (most recent call last):
(nova): TRACE: File "/usr/bin/nova-network", line 48, in <module>
(nova): TRACE: service.serve()
(nova): TRACE: File "/usr/lib/pymodules/python2.7/nova/service.py", line 369, in serve
(nova): TRACE: x.start()
(nova): TRACE: File "/usr/lib/pymodules/python2.7/nova/service.py", line 138, in start
(nova): TRACE: self.manager.init_host()
(nova): TRACE: File "/usr/lib/pymodules/python2.7/nova/network/manager.py", line 812, in init_host
(nova): TRACE: NetworkManager.init_host(self)
(nova): TRACE: File "/usr/lib/pymodules/python2.7/nova/network/manager.py", line 311, in init_host
(nova): TRACE: self._on_set_network_host(ctxt, network['id'])
(nova): TRACE: File "/usr/lib/pymodules/python2.7/nova/network/manager.py", line 890, in _on_set_network_host
(nova): TRACE: network)
(nova): TRACE: File "/usr/lib/pymodules/python2.7/nova/network/linux_net.py", line 456, in ensure_vlan_bridge
(nova): TRACE: interface = ensure_vlan(vlan_num, bridge_interface)
(nova): TRACE: File "/usr/lib/pymodules/python2.7/nova/utils.py", line 613, in inner
(nova): TRACE: retval = f(*args, **kwargs)
(nova): TRACE: File "/usr/lib/pymodules/python2.7/nova/network/linux_net.py", line 467, in ensure_vlan
(nova): TRACE: _execute('sudo', 'vconfig', 'add', bridge_interface, vlan_num)
(nova): TRACE: File "/usr/lib/pymodules/python2.7/nova/network/linux_net.py", line 689, in _execute
(nova): TRACE: return utils.execute(*cmd, **kwargs)
(nova): TRACE: File "/usr/lib/pymodules/python2.7/nova/utils.py", line 169, in execute
(nova): TRACE: cmd=' '.join(cmd))
(nova): TRACE: ProcessExecutionError: Unexpected error while running command.
(nova): TRACE: Command: sudo vconfig add None 100
(nova): TRACE: Exit code: 3
(nova): TRACE: Stdout: ''
(nova): TRACE: Stderr: 'ERROR: trying to add VLAN #100 to IF -:None:- error: No such device\n'

/etc/nova/nova.conf:
--dhcpbridge_flagfile=/etc/nova/nova.conf
--dhcpbridge=/usr/bin/nova-dhcpbridge
--logdir=/var/log/nova
--lock_path=/var/lock/nova
--state_path=/var/lib/nova
--verbose
--s3_host=172.16.3.82
--rabbit_host=192.168.3.1
--cc_host=192.168.3.1
--ec2_url=http://172.16.3.82:8773/services/Cloud
--fixed_range=192.168.0.0/16
--network_size=8
--FAKE_subdomain=ec2
--routing_source_ip=192.168.3.1
--sql_connection=mysql://root:novaroot@172.16.3.82/nova
--glance_host=192.168.3.1
--image_service=nova.image.glance.GlanceImageService
--iscsi_ip_prefix=192.168.