[arch-general] xterm letters show up with strange bars

In fact this happeded weeks before, maybe after upgrading to xorg1.8, when typing in xterm, it left with each letter with an annoying vertical line. [see the image attached] I believe this has something to do with compiz-wm, if I switch to the other window and switch back, those lines gone, but still appear when new letters typed in. And if I switch to the default Metacity wm, nothing annoying any more. Any people encounter such problem? I switch to urxvt instead as the terminal this days. installed packages: [i686] *compiz-core 0.8.6-2 xorg-server 1.8.1-1 xterm 259-1* -- Arch Linuxer, Pythoner, Geek --> Blog: http://apt-blog.net