Description of problem:
Although migrate successfully, But the terminal which brought up virt-manager will appear VirtError message after migrate guest on both source and destination hosts.

Version-Release number of selected component (if applicable):
subscription-manager-1.8.21-1.el5
python-rhsm-1.8.17-1.el5
virt-who-0.7-9.el5
katello-headpin-1.4.3-11.el6sam_splice.noarch
candlepin-0.8.24-1.el6sam.noarch

How reproducible:
50%

Steps to Reproduce:
Rrecondition:
Prepare a pair of host(host1 and host2), guest is running on the host1, run the following cmd in the host3 , Register host1 , host2 and guest1 to stage candlepin server successfully.

virt-who run in the libvirtd mode.
1 In the Terminal1, ssh login to the host1, bring up the virt-manager
# ssh -X root@[host1's ip]
# virt-manager
2 In the Terminal2, ssh login to the host2, bring up the virt-manager
# ssh -X root@[host2's ip]
# virt-manager
3 Make sure the virt-who and libvirtd is running in the host1 and host2
# service virt-who status
# service libvirtd status
4 In the Terminal1, Live Migrate guest1 from host1 to host2 
# virsh migrate --live [guestname] qemu+ssh://[host2's ip]/system

5 Check the pop up message in the terminal1(host1):
[root@hp-z220-08 images]# virsh migrate --live Rhel5.10snapshot5A qemu+ssh://10.66.100.112/system
root@10.66.100.112's password: 
Traceback (most recent call last):
  File "/usr/lib64/python2.4/site-packages/libvirt.py", line 1941, in dispatchDomainEventCallbacks
    cb(self,dom,event,detail,opaque)
  File "/usr/share/virt-who/virt.py", line 74, in changed
    l = self.listDomains()
  File "/usr/share/virt-who/virt.py", line 64, in listDomains
    raise VirtError(str(e))
virt.VirtError: invalid connection pointer in virConnectListDomains
Traceback (most recent call last):
  File "/usr/lib64/python2.4/site-packages/libvirt.py", line 1941, in dispatchDomainEventCallbacks
    cb(self,dom,event,detail,opaque)
  File "/usr/share/virt-who/virt.py", line 74, in changed
    l = self.listDomains()
  File "/usr/share/virt-who/virt.py", line 64, in listDomains
    raise VirtError(str(e))
virt.VirtError: invalid connection pointer in virConnectListDomains

6 Check the pop up message in the terminal2(host2)
[root@hp-z220-07 libvirt-test-API]# Traceback (most recent call last):
  File "/usr/lib64/python2.4/site-packages/libvirt.py", line 1941, in dispatchDomainEventCallbacks
    cb(self,dom,event,detail,opaque)
  File "/usr/share/virt-who/virt.py", line 74, in changed
    l = self.listDomains()
  File "/usr/share/virt-who/virt.py", line 64, in listDomains
    raise VirtError(str(e))
virt.VirtError: invalid connection pointer in virConnectListDomains
Traceback (most recent call last):
  File "/usr/lib64/python2.4/site-packages/libvirt.py", line 1941, in dispatchDomainEventCallbacks
    cb(self,dom,event,detail,opaque)
  File "/usr/share/virt-who/virt.py", line 74, in changed
    l = self.listDomains()
  File "/usr/share/virt-who/virt.py", line 64, in listDomains
    raise VirtError(str(e))
virt.VirtError: invalid connection pointer in virConnectListDomains
Traceback (most recent call last):
  File "/usr/lib64/python2.4/site-packages/libvirt.py", line 1941, in dispatchDomainEventCallbacks
    cb(self,dom,event,detail,opaque)
  File "/usr/share/virt-who/virt.py", line 74, in changed
    l = self.listDomains()
  File "/usr/share/virt-who/virt.py", line 64, in listDomains
    raise VirtError(str(e))
virt.VirtError: invalid connection pointer in virConnectListDomains
Traceback (most recent call last):
  File "/usr/lib64/python2.4/site-packages/libvirt.py", line 1941, in dispatchDomainEventCallbacks
    cb(self,dom,event,detail,opaque)
  File "/usr/share/virt-who/virt.py", line 74, in changed
    l = self.listDomains()
  File "/usr/share/virt-who/virt.py", line 64, in listDomains
    raise VirtError(str(e))
virt.VirtError: invalid connection pointer in virConnectListDomains

Actual results:
see the error message after step5 and step6

Expected results:
It shouldn't appear error message on the terminal.


Additional info: