Enable postdrop for red hat enterprise 5 SELinux


I was trying to send email through alpine on our server, got SMTP
connection broken error message.

I know that SELinux is blocking it because if I enable SELinux
permissive mode. I can send out the email without any problem.

Following is the error message I got from mailog:
Postfix/postdrop[20764]: fatal: setrlimit: Permission denied
Postfix/smtpd[20763]: warning: premature end-of-input on /usr/sbin/
postdrop while reading input attribute name
Postfix/smtpd[20763]: warning: command "on /usr/sbin/postdrop" exited
with status 1
Postfix/smtpd[20763]: fatal: unable to execute /usr/sbin/postdrop

There is also a AVC message saying postdrop was denied.

I tried to add policy for postdrop without success. Can anyone help me
on that?