Current oneiric seems pretty consistent: if the external monitor is connected when the machine is turned on or comes back from suspend, it works. If the machine is inserted in to the dock while powered on, and then the external display is activated, it doesn't set the right mode and it does not work.
Current oneiric seems pretty consistent: if the external monitor is connected when the machine is turned on or comes back from suspend, it works. If the machine is inserted in to the dock while powered on, and then the external display is activated, it doesn't set the right mode and it does not work.