Philip,
> createdb: could not connect to database template1: FATAL: The data
> directory was initialized by PostgreSQL version 7.4, which is not
> compatible with this version 7.3.3.
Looks like you have a 7.3.3 version of postmaster on your system somewhere,
and are trying to start that after doing initdb under 7.4. Hunt down and
remove the duplicate pg executables and you should be fine.
--
Josh Berkus
Aglio Database Solutions
San Francisco