fixed build for >5.4

Hi David! It's been a while since we shared a room in the Storek building. Hope everything is going well :)

I was doing some research on extension writing to make PHP's type system more robust and came across the SPL_Types extension for inspiration. I noticed you're now a lead on this project! :dancer: 

It looks like scant work has gone into this extension, here or on the SVN repo linked on pecl.php.net. The extension as written passes on PHP 5.5 once you've made the fix I added (it's a really simple change).

Did you plan on keeping up with this? I'm definitely interested in a similar project we have going at work right now to make PHP safer. 

Cheers mate, talk to you soon,
Anthony