postmaster crashes on start-up

I just successfully installed postgres-ql on my Win-2K PC, with the following set-up:

  Windows-2000
  cygwin     - 1.3.22-1
  postgresql - 7.3.3-1
  cygipc     - 1.14-1

cygipc runs as an automatic service. But every time I attempt to start the postmaster
(as a service or) manually, it fails to run :-(

postmaster -i -D /usr/share/postgresql/data &

I get the following message:
IpcSemaphoreInitialize: semctl(id=2, 0, SETVAL, 0) failed: Invalid
argument
LOG:  startup process (pid 2472) exited with exit code 1
LOG:  aborting startup due to startup process failure

What am I doing wrong :-( ??
(Yes this is a repeat email, no one answered the first)

Shmuel Kahn