Copy Outgoing mail to an email account

[Chickenwing]

Thank you below post first:
http://www.directadmin.com/forum/showthread.php?t=7119&highlight=copy+outgoing

It can work for copying all outgoing mails to an email account(out@domain.com).
But I found that the received copy mail account(out@domain.com) receive two
same email if sender send to local user account.
For example:
a@domain.com send "email1" to b@domain.com
then out@domain.com receive two same mails "email1"
a@domain.com send "email2" to peter@domain2.com
then out@domain.com receive one mail "email2"

and the /var/log/exim/mainlog like that:
2008-04-03 14:39:35 1JhJ6l-00045I-6W <= a@domain.com H=(Notebook) [192.168.11.30] P=esmtpa A=login:a@domain.com S=1399 id=017801c89555$ee553720$1e0ba8c0@Notebook T="test" from <a@domain.com> for b@domain.com
2008-04-03 14:39:36 1JhJ6l-00045M-AC <= a@domain.com U=mail P=spam-scanned S=1802 id=017801c89555$ee553720$1e0ba8c0@Notebook T="test" from <a@domain.com> for b@domain.com
2008-04-03 14:39:36 1JhJ6l-00045M-AC => b <b@domain.com> F=<a@domain.com> R=virtual_user T=virtual_localdelivery S=1917 ST=local_copy_incoming
2008-04-03 14:39:36 1JhJ6l-00045M-AC => /home/mac/imap/domain.com/outgoing/Maildir/new/ <system-filter> F=<a@domain.com> T=local_copy_outgoing S=1962
2008-04-03 14:39:36 1JhJ6l-00045M-AC Completed
2008-04-03 14:39:36 1JhJ6l-00045I-6W => b <b@domain.com> F=<a@domain.com> R=spamcheck_director T=spamcheck S=1682
2008-04-03 14:39:36 1JhJ6l-00045I-6W => /home/mac/imap/beck.dtdns.net/outgoing/Maildir/new/ <system-filter> F=<a@domain.com> T=local_copy_outgoing S=1559
2008-04-03 14:39:36 1JhJ6l-00045I-6W Completed

it run two local_copy_outgoing transport.
one is for actual sending action
one is spam_check action

Can I set spam_check action just for outside domains email. not for localdelivery?

Thank you.