Dennis pointed out to me that there is a quick way to switch to portrait orientation in the BlackBerry Simulator. According to him this little gesture also works in the older simulator but its the first I have heard of it. To switch to portrait mode you simply need to swipe from the bottom right corner of the bezel towards the center of the device. To swipe just click down on the mouse button and hold it down as you drag.
My simulator is acting up on my laptop so I have not had a chance to try it myself but I had two other devs try it out and it worked. Let me know if it works for you too.