how to run a program in .forward?

[Song Jianping]

Hello all,

As i want to do some special processing on my mail, i write a program
named "myprog". Then i put it in .forward as "| myprog".
When i test it with "/usr/sbin/sendmail -v MYNAME < testmail", sendmail
reports that:
Connecting to prog... Service not available.

I am using RedHat6.0.

Can anyone tell me how to do the job as i described above?

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Best Regards
Song                                     mailto:[EMAIL PROTECTED]