nova-conductor error(grizzly-g3)

when i start nova-conductor service with grizzly-g3, i found below error:

2013-03-22 01:54:20.933 ERROR nova.openstack.common.rpc.amqp [req-cc73b4fd-1286-4f25-8bab-130be4b27669 None None] Exception during message handling
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp Traceback (most recent call last):
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp File "/usr/lib/python2.7/dist-packages/nova/openstack/common/rpc/amqp.py", line 393, in _process_data
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp rval = self.proxy.dispatch(ctxt, version, method, **args)
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp File "/usr/lib/python2.7/dist-packages/nova/openstack/common/rpc/dispatcher.py", line 133, in dispatch
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp return getattr(proxyobj, method)(ctxt, **kwargs)
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp File "/usr/lib/python2.7/dist-packages/nova/openstack/common/rpc/common.py", line 420, in inner
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp return catch_client_exception(exceptions, func, *args, **kwargs)
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp File "/usr/lib/python2.7/dist-packages/nova/openstack/common/rpc/common.py", line 403, in catch_client_exception
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp return func(*args, **kwargs)
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp File "/usr/lib/python2.7/dist-packages/nova/conductor/manager.py", line 357, in service_update
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp svc = self.db.service_update(context, service['id'], values)
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp File "/usr/lib/python2.7/dist-packages/nova/db/api.py", line 169, in service_update
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp return IMPL.service_update(context, service_id, values)
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp File "/usr/lib/python2.7/dist-packages/nova/db/sqlalchemy/api.py", line 95, in wrapper
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp return f(*args, **kwargs)
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp File "/usr/lib/python2.7/dist-packages/nova/db/sqlalchemy/api.py", line 439, in service_update
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp service_ref.save(session=session)
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp File "/usr/lib/python2.7/dist-packages/sqlalchemy/orm/session.py", line 405, in __exit__
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp raise
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp TypeError: exceptions must be old-style classes or derived from BaseException, not NoneType
2013-03-22 01:54:20.933 20943 TRACE nova.openstack.common.rpc.amqp
2013-03-22 01:54:20.936 ERROR nova.openstack.common.rpc.common [req-cc73b4fd-1286-4f25-8bab-130be4b27669 None None] Returning exception exceptions must be old-style classes or derived from BaseException, not NoneType to caller

my configure file for nova:

nova.conf:

[DEFAULT]
dhcpbridge_flagfile=/etc/nova/nova.conf
dhcpbridge=/usr/bin/nova-dhcpbridge
logdir=/var/log/nova
state_path=/var/lib/nova
lock_path=/var/lock/nova
force_dhcp_release=True
iscsi_helper=tgtadm
libvirt_use_virtio_for_bridges=True
connection_type=libvirt
root_helper=sudo nova-rootwrap /etc/nova/rootwrap.conf
verbose=True
ec2_private_dns_show_ip=True
api_paste_config=/etc/nova/api-paste.ini
volumes_path=/var/lib/nova/volumes
enabled_apis=osapi_compute,metadata

#sql connection
sql_connection=mysql://nova:nova@host-db/nova

#rabbitmq
rabbit_host=kapi

#auth
auth_strategy = keystone

#glance
glance_api_servers=host-glance:9292

# instance location
#instances_path=/home/instances

# libvirt
compute_driver=libvirt.LibvirtDriver
libvirt_type="kvm"

# libvirt with quantum
libvirt_vif_driver=nova.virt.libvirt.vif.LibvirtOpenVswitchVirtualPortDriver
libvirt_ovs_bridge="br-int"

# vnc specific configuration
vncserver_listen=0.0.0.0

#quantum
network_api_class=nova.network.quantumv2.api.API

# only in compute node
quantum_url=http://host-quantum:9696
quantum_auth_strategy=keystone
quantum_admin_tenant_name=demoTenant
quantum_admin_username=test
quantum_admin_password=123456
quantum_admin_auth_url=http://host-keystone:35357/v2.0

#volume
volume_api_class=nova.volume.cinder.API

libvirt_volume_driver = nova.virt.libvirt.volume.LibvirtISCSIVolumeDriver

anyone can help me, by the way, is there any document about how to install grizzly