It's being fired by a motion detector, but even if there are no more triggers it still stays on. I've seen other reports of this, and it seems to be only when linked to a motion sensor. weird!
In the newest beta it works. I'm using this in LUA with 'On FOR 7' on a KAKU switch, using an RFXCOM tranceiver.
I remember, there were problems with 'On FOR x' in past versions but I don't remember the details.