problems running postmaster

I was going through the steps to install Postgres 6.4.2. The install went
just fine. The next step was to test the server by running:

postmaster -i

but it fails with this warning:

 postgres]$ postmaster -i
IpcMemoryCreate: shmget failed (Permission denied) key=5432010,
size=49164, permission=700
IpcMemoryAttach: shmat failed (Permission denied) id=1
FATAL 1:  AttachSLockMemory: could not attach segment


I've followed the installation instructions step by step. And I've
successfully installed this same version on my machine at home.

Both running RedHat Linux 
Kernel 2.1.125


Any suggestions would be appreciated.


Kevin


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Kevin Heflin          | ShreveNet, Inc.      | Ph:318.222.2638 x103
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