Initdb failing when installing Postgre on Cygwin

Hello,

I am following a guide here:

http://www.ejip.net/faq/postgresql_win_setup_faq.jsp

And when I run this command:

Initdb -W -D /usr/local/pgsql/data

It says creating directory's and stuff and then it gives this error and
quits:

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"

I am using Cygwin version 1.5.5-1. I downloaded Cygipc version 1.14 and
installed it according to that guide. I used the PostgreSQL that came with
the downloaded Cygwin. I am running XP Pro w/ SP1. Thanks.

-Ben Sytko