[exim] Block/reject outgoing mail from some domain

Hi,

I want to block three domain (spam1.com, spam2.com, spam3.com) send
outgoing mail. I have configured exim.conf :

################# Block domain################
domainlist exim_blacklist = lsearch;/etc/eximblacklist
#################### End block############

################# Block domain #######################
reject_domains:

driver = redirect
# RBL Blacklist incoming hosts
domains = +exim_blacklist
allow_fail
data = :fail: Connection rejected: SPAM source $domain is manually
blacklisted.
####################### End block #####################

Everything work fine, but domain spam1.com, spam2.com, spam3.com can't
receive mail . I just want to reject/block outgoing mail but not
reject/block incoming mail.

What error with my configure ? Thank you for your time.