Added options to category_listing.php:
$cat_tree=true;//set to true to display the full tree of category (related categories), otherwise false
$duplicates=false;// Related categories are only shown with matching if they have not been shown already, set this to true to it will show category from tree though its shown already.
Changed Files: category_listing.php

Tested on PHP 4 & 5, SQL 4 & 5, osC 2.2 ms2, rc1 & rc2a and is register_globals compatible.

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