I run dual monitors a lot of the time (my laptop and an external screen).

I turned off my computer, unplugged the external monitor, and turned the computer back on. When Ubuntu loads, the login screen is half on the screen and half off (on the left side). then when I'm logged on, I change the resolution to fit the single screen, but the taskbar items are skewed. (Applications Places System) is located on the top right instead of top left.

My question is: How do I get Ubuntu (Hardy) to recognize that I'm not connected to a second monitor and adjust the resolution accordingly. I never had this problem in windows.