procmail on AIX

I have setup procmail, and when I tried to implement it it fails.
There is an entry in the syslog...

Sep 13 14:44:41 eagle sendmail[74446]: OAA66254: to=|exec /usr/local/bin/procmai
l #spamtest(_at_)mydomain(_dot_)com, ctladdr=<spamtest(_at_)mydomain(_dot_)com> 
(999/1000), delay=00:00:00, xdelay=00:
00:00, mailer=prog, stat=Unknown mailer error 127

does anyone know why this is happening, and how to fix it?

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