Solved smtpd_milter or contents_filter

[m_pahlevanzadeh]

I installed postfix+dovecot and they're work fine.
Also I installed DKIM and it's work fine.
Now I want to install SpamAssassin. I'm confused. I saw in documentations for content filtering and I found two variables in Postfix:

smtpd_milters =inet:127.0.0.1:8891
And 
#content_filter = scan:localhost:10024

Also I found some package and suggestion for anti spam.
Please help me to choose correctly package for SA. Also a good and new documentation for configuration. In above, I have DKIM and smptd_milter is configured for using DKIM.
At first: How can I configure it for multiple milter such as amavis and clamav and SA.
Second, I need to a new documentation for installing for SA over postfix.
Before any suggestion THANK YOU....

 

[atax1a]

you can pass multiple milters to that option by comma-separating them. See the MILTER_README for details.

Milters check the mail at transaction time. the content_filter option checks the mail after the message was accepted, and thus cannot (for example) reject spam at transaction time. See the Postfix FILTER_README for details.