Need manchester decode class/module

I need to decode a signal which uses Manchester
Encoding. That is I am looking for a GNURadio
Manchester Decoding class/module which will convert
the following transitions: 01->1, 10->0. I already
have the signal FM demodulated going thru a slicer.
Does anyone know if there is code to do this stuff? I
can of course write my own C++ block, but prefer to
reuse other peoples code.

Thanks,

George B.
[email protected]