...
Then, go to the end of the file, and add this:
| No Format |
|---|
spamassassin unix - n n - - pipe user=nobody argv=/path/to/spamc -f -e /path/to/postfix/sendmail -oi -f ${sender} ${recipient} |
...
# make sure it's all on one line or |
...
# start the second line with a whitespace |
Then, setup spamd to start with the system, and you are ready to go. If you wish to provide spamassassin preferences, change "user=nobody" to a valid system user (except for root, since Postfix will NOT call external programs as root), and add .spamassassin into that user's home directory.
...