+1, you dont need to flat it with some sand paper, you can just key it with some scotchbrite. as long as its not shiney then the paint will stick. of course if you cant get any scotchbright then you will have to sand it with a high grade paperPrimer before painting, If you sign up there is a great picture guide for this in the guide section.
Don't be a badge w**ker. What is the point?