Policyd sender throttle

==== Required information ====
- iRedMail version: 0.8.7
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): LDAP
- Linux/BSD distribution name and version: CentOS 6.5
- Related log if you're reporting an issue:
====

Dear iRedMail support.
I'm trying to configure policyd (v. 1.82) to enable sender throttle, using the guide:

http://www.iredmail.org/wiki/index.php? … EL.CentOS, but the daemon on port 10032 doesn't start.

I'm confused because the above mentioned guide says to set:
ENABLE_SENDER_THROTTLE="YES"
in /etc/init.d/policyd
but there is no such variable inside.
I tried to include it at the beginning of the init script but it doesn't work.
Looking at the init script, it seems it will never start a second daemon:

start()
{
    echo -n $"Starting $prog:"
    daemon "$POLICYD -c $CONF"
    RETVAL=$?
    [ "$RETVAL" = 0 ] && touch /var/lock/subsys/policyd
    echo
}

Can you please help me to understand what's wrong?

Thanks a lot

Riccardo