[xmonad] IMLayout - properties not working?

[Robert Sawko]

Dear All,

I was wondering if I could ask you to clarify one issue. I am playing
with IM layout for Skype.

This is th relevant passage in my xmonad.hs
chatLayout =  avoidStruts $ withIM (1%6) rooster  Full 
  where
    rooster = And (ClassName "Skype") (Not (Role "ConversationsWindow"))

I took ConversationsWindow from xprop.

The problem is that opening a conversation window still gets opened in
the sidebar and removes the rooster which goes to the main area? What I
am doing wrong? I have seen a number of config files with the above line
but for some reason this doesn't work on my machine. 

Opening other applications works ok.

Any hints will be greatly appreciated,
Robert
-- 
Do you believe in the axiom of choice?
http://en.wikipedia.org/wiki/Banach–Tarski_paradox