As with many Linux projects, the work of implementing Linux-PAM was done by many people. I think it is important to publicly thank them so here is a mostly complete list. A more complete list (I am able to keep it current) is given at the end of the Linux-PAM documentation.
First, we should thank Vipin Samar and Roland J. Schemers III of Sunsoft for authoring the PAM-RFC. Similarly, thanks should be extended to Sunsoft Inc. for their generally open attitude towards the Linux implementation of PAM and especially to their principal PAM engineer, Charlie Lai.
Second, excluding myself, here is a list of all the people that have helped make Linux-PAM a reality: Craig S. Bell, Derrick J. Brashear, Ben Buxton, Oliver Crow, Marc Ewing, Cristian Gafton, Eric Hester, Eric Jacksch, Michael K. Johnson, David Kinchlea, Elliot Lee, Al Longyear, Marek Michalkiewicz, Aleph One, Sean Reifschneider, Danny Sung, Eric Troan, Theodore Ts'o, Jeff Uphoff, Ronald Wahl, John Wilmes, Joseph S. D. Yao and Alex O. Yuriev.