Mine too
Mine has done this for thousands of miles. I have 16,000 miles on my bike, and it runs great. I have played with the light a lot to see what's up..... what I have noticed - it actually thinks it is low. But it also seems to be related to the engine RPM. What I mean is this, if you keep riding it then it will get worse, until it is coming on a lot. When you are riding, if you pull the clutch in and let it coast for a few seconds, the light will shut off again. If you don't let the RPM's fall, then the light will just stay on. It seems as though (this is my own explanation which holds no scientific or engineering premise) the oil is somewhat low, even though it looks at or near the top level. The high RPM's are causing the oil to move faster, possibly even 'foam' up and causes the sensor to think it's low on oil. I'm still worried that when the sensor says it's low - it's not getting any oil, so I'm careful with it. But, if you add oil - the light will go away. So, I started filling the oil up over the top of the window and haven't had any problems at all.
By the way - I don't know if it matters, but it could be related, I use Mobile 1 Fully Synthetic Motorcycle Oil.
So - don't worry about it, just add oil!
-Mav