how to auto start "postmaster"?

Dear sir,
   I am using Redhat Linux 6.2 and postgresql 7.0.
   I want to auto-run "postmaster -i &" after booting
the Linux. I write a shell script in /etc/rc.d/rc4.d
so that it would be run after start up.
"----------------
#!/bin/sh
postmaster -i &
----------------"
   However, I know postmaster cannot be run by "root"
but "postgres".
   What can I do, how to modify the code so that the
script can be run by postgres?
   Please help!!!
   Thank you.



=====
Terence Leung,
       Mobile: 9273 9176
       email: tcmleung@yahoo.com,
       Homepage:http://tcmleung.uhome.net

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