Whats the best way to clean up bird poop that has been baked by the sun onto my car?

[bustmethods]

Its really my fault for letting it sit on the paint for so long and now I've got to deal with it. It does not come off with washing or scrubbing. It is a 2004 car with nice paint, except for the bird poop. Will a clay bar help? Should I wax it with a buffing wheel? Any ideas?