Put this into a separate thread so it doesn't stop
Xastir's main thread. Also make sure configure picks
up support for it on OSX and automatically compiles it in.
This is what Derrick said about it:
"the problem is it needs to be threaded or something,
because you have to explicitly block and wait for any
speech you queue to finish or it will clobber the
buffer when you queue the next item to speak. I never
did the threading, so i never made it configurable on."