Obviously,
It is best to never get paint on good clothes to begin with...but...just two weeks ago, the jerk at Home Depot didn't put the lid on the (expensive) can of paint he mis-matched and the damn thing came off as I was walking down the stairs...and it splashed over a brand new coat and perfectly good jeans.
PineSol, rubbed into the dratted stuff liberally and then washed in warm water with borax got rid of it.
This was an acrylic based paint, for what it's worth. I don't think you can get polyurethane or epoxy out with anything.