[Christ]

Darin - clean the paint around that rust, then apply raw white vinegar a few times over a period of a few hours with a normal paint brush (dab it on). It'll allow you to basically wipe the rust away, then you can clean up and oil/paint/coat whatever's still there.

If you really have time, you can continue the vinegar treatment over a couple days, and it might save any sanding that you might be considering here.

By all means, I'd get it fixed before it turns into an issue, and with rust, it's the sooner the better, ya know.