Description of problem:
During test the Rhel6.5 + Rhevm mode against SAM1.3, When migrate guest, it will pop up error message in the rhsm.log

Version-Release number of selected component (if applicable):
subscription-manager-1.9.7-1.el6.x86_64
python-rhsm-1.9.6-1.el6.x86_64
virt-who-0.8-9.el6.noarch
katello-headpin-1.4.3.19-1.el6sam_splice.noarch
candlepin-0.8.26-1.el6sam.noarch

How reproducible:
Always

Steps to Reproduce:
1. Prepare two RHEL6.5 hosts with latest subscription-manager and virt-who installed. 
Rhel host1 and host2 have been added to Rhevm, And host1 have one guest(vm1)
Our test env as the following:
Rhevm: 10.66.78.64
Rhel host 1: 10.66.100.109
Rhel host 2: 10.66.100.110

2.In the host1, Configure virt-who in rhevm mode as the following:
[root@hp-z220-03 ~]# cat /etc/sysconfig/virt-who 
    VIRTWHO_BACKGROUND=1
    # Enable debugging output.
    VIRTWHO_DEBUG=1
    VIRTWHO_INTERVAL=20
    VIRTWHO_RHEVM=1
    # Option for RHEVM mode
    VIRTWHO_RHEVM_OWNER=ACME_Corporation
    VIRTWHO_RHEVM_ENV=Library
    VIRTWHO_RHEVM_SERVER=https://10.66.78.46:443
    VIRTWHO_RHEVM_USERNAME=admin@internal
    VIRTWHO_RHEVM_PASSWORD=redhat

3.In the host1,retart virt-who service
[root@hp-z220-03 ~]# service virt-who restart
[root@hp-z220-03 ~]# service virt-who status
virt-who (pid  16175) is running...

4. Register the host1 and host2 to SAM server
# Subscription-manager register --username=admin --password=admin

5. Register the vm1 to SAM server
# Subscription-manager register --username=admin --password=admin

6. Monitor the rhsm log :
# tail -f /var/log/rhsm/rhsm.log

7. In the Rhevm's webUI, migrate the vm1 to host2, please see the rhsm.log in the Actually result.

Actual results:
2013-10-08 23:35:01,976 [DEBUG]  @subscriptionmanager.py:89 - Sending update in hosts-to-guests mapping: {'1948ec11-1a18-495a-bc5e-733f4de098a4': [], 'fc31f4db-dfa4-440e-94df-c0c74f913320': ['a25bc871-25af-44a8-8083-a3b321ad808e']}
2013-10-08 23:35:22,438 [DEBUG]  @subscriptionmanager.py:89 - Sending update in hosts-to-guests mapping: {'1948ec11-1a18-495a-bc5e-733f4de098a4': [], 'fc31f4db-dfa4-440e-94df-c0c74f913320': []}
2013-10-08 23:35:42,864 [DEBUG]  @subscriptionmanager.py:89 - Sending update in hosts-to-guests mapping: {'1948ec11-1a18-495a-bc5e-733f4de098a4': ['a25bc871-25af-44a8-8083-a3b321ad808e'], 'fc31f4db-dfa4-440e-94df-c0c74f913320': []}
2013-10-08 23:35:43,107 [ERROR]  @virt-who.py:212 - Error in communication with subscription manager, trying to recover:
Traceback (most recent call last):
  File "/usr/share/virt-who/virt-who.py", line 196, in _send
    result = self.subscriptionManager.hypervisorCheckIn(self.options.owner, self.options.env, virtualGuests)
  File "/usr/share/virt-who/subscriptionmanager.py", line 92, in hypervisorCheckIn
    return self.connection.hypervisorCheckIn(owner, env, mapping)
  File "/usr/lib64/python2.6/site-packages/rhsm/connection.py", line 738, in hypervisorCheckIn
    return self.conn.request_post(url, host_guest_mapping)
  File "/usr/lib64/python2.6/site-packages/rhsm/connection.py", line 544, in request_post
    return self._request("POST", method, params)
  File "/usr/lib64/python2.6/site-packages/rhsm/connection.py", line 469, in _request
    self.validateResponse(result, request_type, handler)
  File "/usr/lib64/python2.6/site-packages/rhsm/connection.py", line 511, in validateResponse
    raise RestlibException(response['status'], error_msg)
RestlibException: undefined local variable or method `hypervisor' for #<Class:0x000000062dd358>
2013-10-08 23:35:43,326 [DEBUG]  @subscriptionmanager.py:89 - Sending update in hosts-to-guests mapping: {'1948ec11-1a18-495a-bc5e-733f4de098a4': ['a25bc871-25af-44a8-8083-a3b321ad808e'], 'fc31f4db-dfa4-440e-94df-c0c74f913320': []}


Expected results:
It shouldn't pop up these error messages.It should only pop up the normally log messages after migrate succesfully as the following:
2013-10-08 23:35:43,326 [DEBUG]  @subscriptionmanager.py:89 - Sending update in hosts-to-guests mapping: {'1948ec11-1a18-495a-bc5e-733f4de098a4': ['a25bc871-25af-44a8-8083-a3b321ad808e'], 'fc31f4db-dfa4-440e-94df-c0c74f913320': []}


Additional info: