Trigger From Log Event

Is there a way (before I write up a script to do it) that I can trigger an action from a log entry?
Specifically, I thought it'd nice to get a Growl/Prowl message if a 'send failed (no acknowledgment)' message came up in the log.

I came up with this;

http://forums.indigodomo.com/viewtopic.php?f=123&t=15356