No need for the simpler code sample.
The code in Runkit_Sandbox was enough
for me to figure out what I was supposed
to be doing.
Well, I see a couple problems in what you've folded in.
#1 Okay, not a problem, just something worth mentioning.... The "FETCHBOX" nomenclature I used in Runkit_Sandbox was just an ohmage to the fact it was fetching a sandBOX object. There's nothing special or (paradoxically enough) generic about that naming. You're welcome to use it, but it doesn't speak to what you're fetching (unless you want to call it a voice box -- yuk yuk yuk)
#2 Only a zend_obj worth of data is being allocated for this object, you need to overrid the create_object method in the zce for your flitetts object it order to allocate the additional room for the voice_ptr pointer, not to mention create a matching object_dtor method to clean up voice_ptr later on.
#3 After taking another look at the way this ext (and the library) works, I wonder if it makes sense to store the voice in an object at all. Looks like you could keep a single instance of a flite-voice in a global (or at least thread-global) variable and let all wav generation use that common voice object. Though maybe I missed something there...
-Sara