I've successfully added my printer via Ubuntu 12.04 default drivers, but it seems the driver doesn't support using papers from the cassette tray even if I set the default preference to use the cassette only. Each time I print the document, I always check this setting, as well as the status of the cassette (there are at least 10 pieces of papers inside).

Screenshot: http://img39.imageshack.us/img39/8128/screenshotfrom201211191.png

The warning message I receive from the printer is that there is no paper at the REAR tray! I don't have such issues with my Windows 7 Pro.

Please advise. Thanks!