some question for cacti plugins(syslog & realtime)

[raxe]

Q1:
i'v read file README to install "realtime", but i can not unstand "Edit your include/global.php and add it to your $plugins list, and you are rolling."

OS : FreeBSD 9.1
cd /usr/local/share/cacti/include
and find global.php, but i don't know how to add $plugins list or where can i add , or what should i add to

i hope someone can give me a sample that i can read

Q2:
after i install plugin"syslog"
and check with " #tcpdump -tlni em0 port 514" ensure that device sand syslog to my server.
but cacti can not show log on web
and i check mysql database, thers is no data input.
so i want to ask : how plugin get syslog into mysql server?