UserParameter=pptp.listen,/etc/zabbix/pptp.sh
UserParameter=l2tp.listen,/etc/zabbix/l2tp.sh

vpn:/etc/zabbix# ls -l
total 16
-rwxr-xr-x 1 root root  118 2012-02-01 14:36 l2tp.sh
-rwxr-xr-x 1 root root  164 2012-02-01 15:24 pptp.sh
-rw-r--r-- 1 root root 1121 2012-02-01 13:59 zabbix_agent.conf
-rw-r--r-- 1 root root 2585 2012-02-01 15:28 zabbix_agentd.conf