Fix verified in lvm2-2.02.56-8.el5_5.4/lvm2-cluster-2.02.56-7.el5_5.3.
I filtered out existing devices, vgscaned, and verified that those devices were removed from the .cache files on all nodes in the cluster. I then did the opposite and verified that those devices reappeared in the .cache file.
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on therefore solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.
http://rhn.redhat.com/errata/RHBA-2010-0432.html