initdb failing: Invalid binary "/usr/bin/postgres"?

Greetings all...

I'm in the process of setting up Cygwin/PostgreSQL (7.2.1-2) on a
Windows XP Professional machine, and am having trouble running initdb.
Here's what's happening (Note: I'm logged in as the postgres user when
I execute the following command. Also, ipc-daemon is running, and was
started with "ipc-daemon&"):

$ initdb -D /usr/share/postgresql/data
The files belonging to this database system will be owned by user
"postgres".
This user must also own the server process.

Fixing permissions on existing directory /usr/share/postgresql/data...
ok
creating directory /usr/share/postgresql/data/base... ok
creating directory /usr/share/postgresql/data/global... ok
creating directory /usr/share/postgresql/data/pg_xlog... ok
creating directory /usr/share/postgresql/data/pg_clog... ok
creating template1 database in /usr/share/postgresql/data/base/1... ok
creating configuration files... ok
initializing pg_shadow... FindExec: invalid binary "/usr/bin/postgres"
FATAL 1:  /usr/bin/postgres: could not locate executable, bailing
out...

initdb failed.

If I go and look in /usr/bin, I find postgres.exe, and postmaster
(Which is a symlink to postgres.exe).

Has anyone seen this before? Can anyone point me in the direction of
some information regarding this problem?

Any help would be greatly appreciated...

Cheers...

Dave Bruzzone