trigger template don't work

[amcorreia]

I have

2 templates:

Modelo_ping_t wich have item for monitoring host through ping, and a trigger
{Modelo_ping_t:icmpping.last(0)}=0
and
dmz_t which have others items and with none trigger.

and I have an action for:
Trigger = "{Modelo_ping_t:icmpping.last(0)}=0".

and the host fw1a, if fw1a is down, the trigger is act, but the action don't is actived.
if I add a trigger for host fw1a and an action for this, its work fine.

this is a bug?