In a new post to his blog, Matthew Weir O'Phinney talks about a method for overloading arrays in a script written for the PHP 5.2 series.

Several weeks back, a bug was reported against Zend_View that had me initially stumped. [...] I'd read about this some months back on the php internals list, but at the time hadn't understood the consequences.

Basically, __get() no longer returns a reference and returns values in read mode, which makes modifying arrays using overloading impossible using traditional methods.

Unfortunately, this was exactly the functionality that was needed, so Matthew set out to find a way to do just that. His initial method, extending the ArrayObject, worked but still gave errors. On Mike Naberezny's recommendation, though, this too was resolved with a simple call to the __set method instead.