ARG Separation for Get Vars

I remember some discussion a while back for adding the option of separating GET vars in the query string with ";" rather than "&". I'm on a big XHTML compliance kick right now, and after doing some basic testing (which worked because PHP is so flexible), I realized my vars (if more than 1 ;) ) are getting encoded as a big string like: array(1) { ["MessageId"]=> string(26) "144;sid=993634620246677112" } hehe.. obviously not what I'm looking for. I remember the feature to make this work got implemented at 1 point (I think), but what is the php.ini config switch to turn this on? Tried to RTFM but couldn't find it. ;) Any help? -Brian Tannenr