Sun is known for both its great RISC hardware platform and its own UNIX
operating system series. One of our customers uses PostgreSQL on Solaris 10 and along with PostgreSQL's "ident" authentication method. For the authentication daemon, they chose pidentd. ( http://www.lysator.liu.se/~pen/pidentd/ )

For those who don't know what an ident service does, here's a little summary: http://www.postgresql-support.de/blog/blog_zoltan.html