I don't think you can pass around references to functions as such, but you can use variable interpolation to an extent to achieve that effect:

http://www.phpbuilder.com/lists/php3...99903/0527.php

That's from PHP 3 though, no idea if that behaviour still works.

Out of interest, why would you want to do this anyway? I've been using PHP for several years and have never come across a situation where I'd need to pass in a reference to a function.