Added check to see the change listener has already been added, removes it if it has.
Added check to see the change listener has already been added, removes it if it has.


git-svn-id: 8ebed0c25533aaea68ca43268d4d516467f97e6a@8250 6e01202a-0783-4428-890a-84243c50cc2b

concord-consortium/otrunk,concord-consortium/otrunk