Well I investigated this. It only has store and retrieve methods (i.e. for data serialized to file) not freeze/thaw. I did not test the retrieve function, but it looks pretty straightforward--it parses the file and uses a php unserialize function to put it back into a data structure.

I tried to see if I could feed the frozen object to that function, because I suppose in principle that out to work. Unfortunately it expects a string and the frozen object is binary, and I'm not enough of a php wizzard to figure out how to decode it two bytes at a time to a string--if that's even possible.