As in most cases and also found in the support-topic: the 1.6 version does not work.

Because the 1.5 version is a stable one I use this all the time.

What is new or what has changed in 1.5.1:
I've removed some bugs found in the support topic regarding duplicate Meta-description and duplicate Meta-keywords.
Changed also is the Meta-description on the index.php.
I've also changed the lenght of the meta_create_title as in most cases the was to short.

Please read the changelog.txt for details.

Support-topic can be found here: http://forums.oscommerce.com/index.php?showtopic=134546

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