[xmonad] XMonad.Hooks.UrgencyHook broken?

Hi, I have tried using XMonad.Hooks.UrgencyHook but can't get it to work -- despite following the docs for it. In my ~/xmonad/xmonad.hs file, I have main = xmonad $ withUrgencyHook dzenUrgencyHook { args = ["-bg", "darkgreen", "-xs", "1"] } Yet when chatting via pidgin, which would send such an urgency hook, xmonad doesnt react to it. What's the best way of testing this? Is there something else i need to be doing to get this to work? i heard that rxvt-unicode can generate urgencyhook stuff -- how? Thanks! David.