libvirt users - Jun 2011 - old, deleted LUN still showing up after a virsh pool-refresh

Today I upgraded one of our KVM physical host servers to Centos 5.6. 
The other server remains on Centos 5.5.  I've configured a storage pool 
in libvirt to use LUNs from an iscsi storage system as the volumes for 
each VM.

After the upgrade, I decommisioned one of the VMs and removed the LUN 
from the storage system.  Normally after this kind of operation, I 
simply need to run this command and the server will see that the LUN no 
longer exists and remove the volume.

# virsh pool-refresh --pool=dev-kvm-storage
Pool dev-kvm-storage refreshed

This works fine on the centos 5.5 host, but the centos 5.6 still lists 
the old lun in the vol-list and displays zeros for the capacity.

# virsh vol-info 7.0.0.26 --pool=dev-kvm-storage
Name:           7.0.0.26
Type:           block
Capacity:       0.00
Allocation:     0.00

Do I need to do something different now for the newer version of libvirt 
that is included with centos 5.6?

Here are the kernel and libvirt versions I'm using:

Centos 5.6:
kernel-2.6.18-238.9.1.el5
libvirt-0.8.2-15.el5_6.4

Centos 5.5:
kernel-2.6.18-194.26.1.el5
libvirt-0.6.3-33.el5_5.3

Any help is greatly appreciated.