[Xmonad] slock issue

Hi, all. I have strange issue with slock [0]. Here is how it's bound in my Config.hs: ((modMask, xK_F12 ), spawn "slock") -- @@ Lock screen Dead simple. But it doesn't work. When i launch slock from urxvt or dmenu everything works. When i launch it using modMask + xK_F12 screen goes black and then after few seconds everything comes back and no locking occurs. I noticed that if for ex. before launching slock my urxvt is in focus and i type something when screen is black, urxvt catches my input. Seems like slock fails to lock screen and catch all input events. But this happens only when i launch slock with a keybinding. Can someone help? [0] http://www.suckless.org/wiki/tools/xlib -- Alexander Tsamutali