Problem with PostgreSQL on Win2K (ipc-daemon)

I've installed PostgreSQL 7.0.3 on Windows 2000 Professional, following the
instructions in the page http://people.freebsd.org/~kevlo/postgres/portNT.html
Everything goes well until the last steps: run the PostMaster.
When I run the ipc-daemon and postmaster the output is the next:

------------------------------------------------------------------------------
-
administrador@JCRAMOS /
$ ipc-daemon &
[1] 848

administrador@JCRAMOS /
$ postmaster -i &
[2] 780

administrador@JCRAMOS /
$ c:\pgsql703\usr\local\pgsql\bin\postgres.exe: ***
recreate_mmaps_after_fork_fa
iled
Startup failed - abort
NOTICE: IpcMemoryDetach: shmdt(0x0x4d90000): Invalid argument
NOTICE: IpcMemoryDetach: shmdt(0x0x4c60000): Invalid argument
NOTICE: IpcMemoryDetach: shmdt(0x0x4c50000): Invalid argument

[2]+ Exit 1 postmaster -i
------------------------------------------------------------------------------
-

Of course, postmaster doesn´t run and I can´t continue. Could you help me?

Thanks.