google了一下发现还有遭此厄运的朋友,http://linux.hiweed.com/node/2704。看其回帖,执行xfdesktop命令后,问题解决。呵呵,似乎早该想到这点,Xfce4.2用户手册Components of Xfce 4一节里有写:
看来想象力还不够丰富啊。自嘲一把。xfdesktop
Desktop background manager. This program sets the background image and/or color, and provides a root window menu, a menu panel plugin and a menu editor.