Reading this thread, i ask myself and you why not using a established package format like RPM http://en.wikipedia.org/wiki/RPM_Package_Manager , deb-format or some other out of the linux - environment, compared on http://kitenet.net/~joey/pkg-comp/
 
Or if you are afraid of high complexity and efford to support such a format on all plattforms - then give the PEAR-or PECL-format a chance.
I don't want to say any of these formats meets the requirements, but i did not have seen this formats discussed.
 
What do you think about an more generaly used format for Drupal-packages?
 
 
Best
Thomas Zahreddin
Krüzastr. 18/15
 
A-6912 Hörbranz
 
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