how do I enable the rotate checkbox in fb1280x1024?

I must boot using fb1280x1024.
the screen resolution dialog has all choices greyed out.
rotate screen should be a gimme for fb - it should always work;
is there a config file I can edit to enable this?

another fb problem:
the screen power off slider slides, but does nothing -
the screen never even goes to standby.
(all these work in windows)

Thanks