PHP 5.3.0 and the "global" keyword

This had me stumped for a while - using some 3rd party code with PHP 5.3.0, the "global" keyword didn't seem to work any more (references to the supposedly "global" variable from within functions always gave NULL)..

You have to declare the variable as "global" before setting it in the outer scope - then it works again.

So, this used to work (but doesn't under PHP 5.3.0) :

$util = new Utility();
global $util;
function show() {
    global $util;
    echo "$util->version";
}

but if you swap the lines of the declaration of $utils, then it does work under PHP 5.3.0 :

global $util;
$util = new Utility();
function show() {
    global $util;
    echo "$util->version";
}