Ruby2 compatible

Here is a pull request for your consideration. One caveat: there's still a bug outstanding on Ruby-2.0.0-preview2 that I've filed: https://bugs.ruby-lang.org/issues/7648. 

I think it's worth waiting for a response there. I'll update you with what I find. In the mean time, this patch has proven to work on Ruby 1.8.7, 1.9.2, and 1.9.3 using RVM.

"Theatricality and deception are powerful agents to the uninitiated... but we are initiated, aren't we Bruce?" -- Bane