initdb failing on win xp

Greetings,
i apologize in advance as I'm aware that this error has been addressed in several past posts, but the fixes described have not worked for me.

I installed postgresql from cygwin and its necessary packages successfully.

I installed ipc-daemon2 as an NT service successfully

I created a new user and logged into Windows XP as that user

I allowed my new user to logon as a service

I created a data directory and change the permissions to make my new user the owner

I installed postmaster as an NT service

A problem came when I ran initdb -D /usr/share/postgresql/data

The following resulted:

The files belonging to this database system will be owned by user "postgres".
This user must also own the server process.

The database cluster will be initialized with locale C.

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
selecting default max_connections... 10
selecting default shared_buffers... 50
creating configuration files... ok
creating template1 database in /usr/share/postgresql/data/base/1... FATAL: coul
d not create shared memory segment: Function not implemented
DETAIL: Failed system call was shmget(key=1, size=1081344, 03600).

initdb: failed

I am having a problem finding any other solutions for this error. Any help would be gratefully appreciated.

-dave