[arch-general] openoffice does not work

Hi, I'm a new user of Arch. I've installed openoffice via pacman. However, it doesn't work anyway. Accoring to the Arch Wiki, I added 'OOO_FORCE_DESKTOP=gnome' into my ~/.bashrc, but nothing changed. Clicking at the OOo items in the desktop menu, nothing happens. Then when I tried to run OOo from the terminal using command "$/usr/bin/soffice", error info is: ------------------- no suitable windowing system found, exiting. ------------------- I just don't know what is the matter.