hello!

I am trying to setup automated incoming mail processing and run into the following problem - can't setup procmail + postfix integration

main.cf:
mailbox_command = /usr/bin/procmail

.procmailrc:
:0 fw:
* ^Subject:.*test
| /path/to/mail/processing/script

nothing happens.
mail with subject set to "test" arrives successfully, no any processing takes place.

attempt to debug - change main.cf
mailbox_command = /tmp/1.sh

where /tmp/1.sh:

#!/bin/sh

echo "hello" > /tmp/hello.txt

attept to send email - mail with subject set to "test" arrives successfully, no hello.txt in /tmp/

ls /tmp/h*
ls: /tmp/h*: No such file or directory

Any ideas on what's going on?
Thanks in advance!

Do your maillogs show anything?

well, I am close to newbie with postfix, and can't say for sure
here is my tail from the /var/log/maillog for test message receiving

postfix/smtpd[4176]: connect from fg-out-1718.google.com[72.14.220.153]
postfix/smtpd[4176]: E1E84CE8072: client=fg-out-1718.google.com[72.14.220.153]
postfix/cleanup[4180]: E1E84CE8072: message-id=<1789729710.20081107102701@gmail.com>
postfix/qmgr[29037]: E1E84CE8072: from=<mymail@gmail.com>, size=2078, nrcpt=1 (queue active)
lmtpunix[3190]: accepted connection
lmtpunix[3190]: lmtp connection preauth'd as postman
master[4183]: about to exec /usr/lib/cyrus-imapd/lmtpd
lmtpunix[3190]: IOERROR: fstating sieve script /var/lib/imap/sieve/a/admin/defaultbc: No such file or directory
lmtpunix[3190]: duplicate_check: <1789729710.20081107102701@gmail.com> user.admin 0
lmtpunix[4183]: executed
lmtpunix[3190]: duplicate_check: <1789729710.20081107102701@gmail.com> user.admin 0
lmtpunix[3190]: mystore: starting txn 2147491066
lmtpunix[3190]: mystore: committing txn 2147491066
lmtpunix[3190]: duplicate_mark: <1789729710.20081107102701@gmail.com> user.admin 1226042574 12312996
lmtpunix[3190]: Delivered: <1789729710.20081107102701@gmail.com> to mailbox: user.admin
postfix/lmtp[4182]: E1E84CE8072: to=<admin@mydomain.com>, relay=mydomain.com[/var/lib/imap/socket/lmtp], delay=0.11, delays=0.09/0/0/0.01, dsn=2.1.5, status=sent (250 2.1.5 Ok)
postfix/qmgr[29037]: E1E84CE8072: removed

what means the presented IOERROR?
But no any mention of even attempt to execute /tmp/1.sh script or do something with mailbox_command!
Thanks in advance!