Oh my god it will be a really long work...

Are you sure it can't be done with an simple editing ? ^^
I've check the two versions of the "Search.php" page. They are identic. Where can I have a look to check the code modifications between the two versions (mine and the nightly build) ?
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Normaly the bug is very old because we had it on a older version of ZenPhoto. Then you had tell me that the next version has corrected the bug. It was more than one year ago ^^
I've chosen to install the more stable recent version. Can't you know if my version has the bug ?
The problem could come from my Php version ?