[Webdev] PHP - register globals = off, yes/no?

[Donncha O Caoimh]

Since the days of PHP3 we've used registered global variables in our PHP 
scripts. Of course, most of our development is still in PHP3 land so that 
hasn't changed much.. 
Now though, more development will happen on a PHP4 box and I'm interested in 
turning off "register globals".
A quick Google search[1] found an interview with Rasmus[2] who disagreed with 
turning them off, as "It adds very little to the overall security of an 
application." but reading the manual page[3] it makes logical sense to me to 
break up where your variables come from. 
The downside is you're restricted somewhat in tricks you can play to get over 
the limitations of the browser (logging into a remote server via an invisible 
image springs to mind. If the remote server expects POST variables, the login 
script would have to copy the GET variables into the POST array.)

So, has anyone turned "register globals" off and lived to tell the tale? And 
if so, is it worth the hassle?

[1] http://www.google.com/search?q=php+register+globals+off+why
[2] http://www.webmasterbase.com/article/767/41
[3] http://www.zend.com/manual/security.registerglobals.php

Donncha.