I have found a way to reproduce this bug always now. Its very easy! First I must say Im very sorry if this is already known for reposting it but here it goes! First download that software braek, its a simple software that produces a crack looking thingy to the screen. Now make a shortcut to the desktop for braek, then make a shortcut for the phone and the X-terminal on the left side of the screen. Now open braek and start quickly tapping the area where the phone shortcut lies. Now the phone opens. Close phone software normally and N900 is locked to portrait... you can use Xterminal to kill braek by typing killall braek Tada forced portrait and works always for me. Some software dont like it though. You can open and close the keyboard as you wish and its locked in portrait. To get it back to landscape without restarting phone just open the phone software and close it normally and it goes to portrait.