Rule of thumb, try to never paint over a shiny surface(of any kind) without doing some sort of prep. You have to break the surface sheen by either uniformly sanding with a light grit(220) or priming with a good sandable-type primer. I prefer to use Gripper primer on everything to provide uniformity and adhesion. Plus I ALWAYS prefer to prime vs. sanding (unless there is surface imperfections of some sort)mainly because of cleanliness(because you know that dust will somehow find it's way into your paint finish!!) Gripper is sold at Home Depot, by the way.. --Dave

QUOTE: Do I need to sand before I paint? Or what? The current finish does have a slightly raised texture. Well, if you are wanting a smooth painted wall finish , then yes you would need to sand away "ALL" of the little lumps and bumps of the raised paint. I would suggest using an electric sander. The work would go much faster for you. As far as the grit of paper to use, that would depend on how raised is raised on the finish. I would at least start out with a 180- medium grit. Be careful using the sander . Keep it moving all the time and watch your approach to prevent any gouges. After you have finished sanding, wipe away all of the sanding debris and reprime your walls. Don't forget to wear a mask. For your smooth wall surface, 3/8th would be fine. Purdy dralon ; corona brushes.

I did find a method online that allows the use of oil-based paint to do a crackle-type finish. It involves a layer of oil paint as a base coat, followed by a layer of water-based white glue, like Elmers. Then you go over it with a layer of milk-paint, followed by an oil-based glaze after it's dry. I like this idea as milk paint colors are usually nice historic looking colors, and there won't be as many to choose from so it will make the choice easier. That's where I have usually have the most trouble, and it will be easier to choose from 20 colors than from 1000 :-) I'm going to try a sample board first to make sure it will look the way I want it to. I have a piece of oiled oak in the basement that came from my son's old desk, I think it was a shelf that never got used. I'll treat that to the kind of cleaning you all recommended, and then test the painting technique on it. Now to choose a color and get started! Thanks all! Here is a link that might be useful: Antique Paint Finish

No one's answered so I'll toss in that I use spray paint quite a bit for things like this. Tape it off, protect what you need to protect, and spray away. So easy.