Get error during initdb

Any suggestions as to why I can not initialize the database (see error
below) are greatly appreciated.

I am new to PostgreSQL. I am using W2K, Cygwin, and within Cygwin
PostgreSQL 7.4.1-2.

Olaf

omeding(at)santorini ~
$ initdb -D /usr/local/pgsql/data
The files belonging to this database system will be owned by user "omeding".
This user must also own the server process.

The database cluster will be initialized with locale C.

creating directory /usr/local/pgsql/data... ok
creating directory /usr/local/pgsql/data/base... ok
creating directory /usr/local/pgsql/data/global... ok
creating directory /usr/local/pgsql/data/pg_xlog... ok
creating directory /usr/local/pgsql/data/pg_clog... ok
selecting default max_connections... 10
selecting default shared_buffers... 50
creating configuration files... ok
creating template1 database in /usr/local/pgsql/data/base/1... FATAL: could
not create shared memory segment: Function not implemented
DETAIL: Failed system call was shmget(key=1, size=1081344, 03600).

initdb: failed
initdb: removing data directory "/usr/local/pgsql/data"

omeding(at)santorini ~
$