ping not performed due to setting

[fristi]

With the latest cacti version 0.8.7b we are experiencing problems when using an icmp ping. It doesn't want to execute, in the logs we find :

There are no items in your poller for this polling cycle!
PING: Ping not performed due to setting.

what could be the problem for this item ?

Many thanks,
Lieven Stubbe
Belgian Railways