Cascading windows are gone

I'm trying to figure out how to get my cascading windows back in Photoshop 13. When I select the Window tab the cascade, float all window, float all in window, consolidate all to tabs selections are in gray. If I go to preferences the enable floating docking window docking is checked. I've restarted  but I'm still unable to get the cascading images that I'm use to working with. Any suggestions would be appreciated.