i duno whether he means he doesn't know how he did it, but you can either just strate out declare that variable, or:
<?php
$s = new someclass;
class someclass{
var $boo = 'hi';
}
$s1 = new someclass1;
class someclass1{
var $g;
function someclass1(){
global $s;
$this->g = $s;
}
}
echo $s1->g->boo;
?>
I've never had any need for this, I've either done without, or just extended the class