Unknown problem

For some reason.. i set the procmailrc correctly, and also the forward
file. but for some reasons the mail gets lost and when i run it in
manuel mode by   cat /var/spool/mail/alpha | procmail .procmailrc
and it sends it all to mbox (default) 

What can be wrong??

here is the system info:

SunOS spock 4.1.3 3 sun4c