Problem with Host Down Alert Mail

[gpetruzzi]

Hi,

I am using Cacti version 0.8.7g, and i need that the host from the monitor tab , keep sending alert mails while it is down.
I know that using SNMP , i can use the THOLD plugin to send alerts while is down. The problem is that i cant use SNMP with
some hosts becuase they are behind firewalls that i don´t manage , i can only ping them.
Hope you understand my need.

Thanks in advance .
Willy