[xmonad] xmonad does not work well with "lxpanelctl run"

No matter bind "lxpanelctl run" to some key or run it in xterm, the corresponding dialog will appear, and the cursor can be put in the textbox. However, nothing can be inputted. Instead, the input characters will appear in the xterm which the command is running in. Moreover, "lxpanelctl menu" works fine when run from xterm, but does nothing when binded to a key. I am not saying that, that is a bug of xmonad, but the lxpanelctl works fine with the other wms, e.g., openbox, xfwm4, sawfish,... versions: lubuntu 12.04 lxpanel 0.5.8 xmonad 0.10