[Zope] Reindex of catalog - keep getting ConflictErrors ?

[Gitte Wange]

Hello,

I have a ZCatalog (in the shape of a portal_catalog in CMF).
Everytime I go to the Advanced tab and tries to reindex the catalog, I get 
this error and traceback:
ZODB.POSException.ConflictError
Sorry, a site error occurred.

Traceback (innermost last):

    * Module ZPublisher.Publish, line 150, in publish_module
    * Module Products.Localizer, line 58, in new_publish
    * Module ZPublisher.Publish, line 127, in publish
    * Module Products.Localizer, line 58, in new_publish
    * Module ZPublisher.Publish, line 127, in publish
    * Module Products.Localizer, line 58, in new_publish
    * Module ZPublisher.Publish, line 127, in publish
    * Module Products.Localizer, line 58, in new_publish
    * Module ZPublisher.Publish, line 122, in publish
    * Module Zope.App.startup, line 142, in zpublisher_exception_hook
    * Module ZPublisher.Publish, line 102, in publish
    * Module Zope.App.startup, line 200, in commit
    * Module ZODB.Transaction, line 235, in commit
    * Module ZODB.Transaction, line 349, in _commit_objects
    * Module ZODB.Connection, line 391, in commit
      __traceback_info__: (('Products.Transience.Transience', 'Increaser'), 
'\x00\x00\x00\x00\x00\x00\x00\x06', '')
    * Module Products.TemporaryFolder.TemporaryStorage, line 134, in store

ConflictError: database conflict error (oid 0000000000000006, serial was 
0350b50baca92b4c, now 0350b50a6e739abb)

Why is that ?
-- 
Gitte Wange
Technical Manager

Email: gitte at mmmanager.org
Web: http://www.mmmanager.org
Tlf: +45 36 46 20 02

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is, until you uncover the secret that lets you do what
you wanted it to in the first place.

    -- somebody describing the Zope experience to Jon Udell