CentOS - SpamAssassin and Exim

1. Install Spamassassin [SSH]:
sudo yum install spamassassin

2. Create file filters in /etc/exim/ folder with code:
if $h_X-Spam-Flag: contains "YES"
then
    headers add "Old-Subject: $h_subject"
    headers remove "Subject"
    headers add "Subject: ***[SPAM]*** $h_old-subject"
    headers remove "Old-Subject"
endif

3. In etc/exim/exim.conf after this line:
# $Cambridge: exim/exim-src/src/configure.default,v 1.14 2009/10/16 07:46:13 tom Exp $

put this line:

system_filter = /etc/exim/filters

4. In etc/exim/exim.conf replace:
#spamd_address = 127.0.0.1 783

with:

spamd_address = 127.0.0.1 783

5. In etc/exim/exim.conf replace:
# Bypass SpamAssassin checks if the message is too large.
#
#accept  condition  = ${if >={$message_size}{100000} {1}}
     #add_header = X-Spam-Note: SpamAssassin run bypassed due to message size

# Run SpamAssassin, but allow for it to fail or time out. Add a warning message
# and accept the mail if that happens. Add an X-Spam-Flag: header if the SA
# score exceeds the SA system threshold.
#
#warn    spam       = nobody/defer_ok
       #add_header = X-Spam-Flag: YES
       #add_header = X-Spam-Subject: [SPAM] $h_Subject

#accept  condition  = ${if !def:spam_score_int {1}}
       #add_header = X-Spam-Note: SpamAssassin invocation failed

# Unconditionally add score and report headers
#
#warn    add_header = X-Spam-Score: $spam_score ($spam_bar)n
                    #X-Spam-Report: $spam_report

with:

# Bypass SpamAssassin checks if the message is too large.
  #
  # accept  condition  = ${if >={$message_size}{100000} {1}}
  #         add_header = X-Spam-Note: SpamAssassin run bypassed due to message size

  # Run SpamAssassin, but allow for it to fail or time out. Add a warning message
  # and accept the mail if that happens. Add an X-Spam-Flag: header if the SA
  # score exceeds the SA system threshold.
  #
   warn    spam       = nobody/defer_ok
        add_header = X-Spam-Flag: YES
  #
  accept  condition  = ${if !def:spam_score_int {1}}
        add_header = X-Spam-Note: SpamAssassin invocation failed
  #
  
  # Unconditionally add score and report headers
  #
  warn    add_header = X-Spam-Report: $spam_report

6. Check this code exist in /etc/mail/spamassassin/local.cf
# These values can be overridden by editing ~/.spamassassin/user_prefs.cf 
# (see spamassassin(1) for details)

# These should be safe assumptions and allow for simple visual sifting
# without risking lost emails.

required_hits 5
report_safe 0
rewrite_header Subject [SPAM]
required_score 1.3

7. Restart Spamassassin [SSH]:
/etc/init.d/spamassassin restart

8. Restart Exim [SSH]:
service exim restart