Moises Silva 
<moy@sangoma.com>
http://www.moythreads.com/
- Author and primary developer.

Alexandre Cavalcante Alencar
<alexandre.alencar@gmail.com>
- Debian build, documentation, r2test enhancements and testing in Brazil.

Cleiber Marques da Silva
<cleibermarques@hotmail.com>
- Implementation of collect calls, release forced and other work for the Brazilian variant.

Humberto Figuera
<hfiguera@gmail.com>
- Venezuela variant and immediate accept for the backward side.

Steve Underwood 
<steveu@coppice.org>
- I Borrowed code from his SpanDSP LGPL library for the MF Detector and generator (basically r2engine.c and r2engine.h).

Tzafrir Cohen
<tzafrir.cohen@xorcom.com>
- Debian package.

Afonso Zimmermann
<afonso.zimmermann@gmail.com>
- Test equipment category fix.

