I'm afraid I have no idea how to remove color that has run.
I would recommend next time you wash a quilt that hasn't been washed, or even several times, to use the Color Catchers that are in the detergent aisle.
You might try lemon juice on the affected areas and lay in sunshine. I use peroxide for scorch marks, so you could also try peroxide and sunshine. (Both were used in the 60s for hair bleach.)
If you can, you might overdye the whole quilt in a similar (pale) color (tye-dye), or if it isn't much, perhaps applique over the "runs" (butterflies or flowers or something that would go with the theme of the quilt).
Someone might know if Grandma's Secret Spot Remover would work. El advertises it on her show on RFD tv.
You also might try soaking the quilt in a detergent with stain remover in it. Also, use a Color Catcher. It might lighten the stain and all the other colors, but it might be worth it.
Or, you could say "it won't be seen from a speeding car" or "will it matter in the long run?"
So sorry I don't have the miracle answer you are hoping for. Perhaps someone will, and I can learn from them, too!
This post has been edited.
7/7/2010 2:09:23 PM