There's a bug in changeOwnership, which was reported several times to this list, even with the one-line patch needed... without any effect so far... I've seen your message too.

This bug prevents changeOwnership to do anything if you already own the object on which you apply it. Thanks for your reply, but as I've seen on your previous messages, this bug occurs only when the new owner owns something on the folder where the changeOwnership is supposed to be applied. Since the folders and the objects inside them have always the same owner, there is no reason for this bug to occur. In fact, the ownership is changed, but I cannot reindex the object because I get that strange error message I've previously described.