I tried for a long time to get it working and then gave up: http://forum.linuxmce.org/index.php/topic,12928.0.html
After a couple of brute force attacks against the Asterisk server I installed Fail2ban per the wiki which seems to work against this sort of attack (and I have locked myself out a couple of times!): http://wiki.linuxmce.org/index.php/Fail2ban_-_A_tool_against_brute_force
After a couple of brute force attacks against the Asterisk server I installed Fail2ban per the wiki which seems to work against this sort of attack (and I have locked myself out a couple of times!): http://wiki.linuxmce.org/index.php/Fail2ban_-_A_tool_against_brute_force