My mom used to boil up a large pan of water, big enough to hold the fabric, dump in a whole bunch of cider vinegar, stir, add the unfolded fabric, stir (she had a wooden spoon for that) and just keep stirring every 15 or 20 minutes until the water was cold. Drain, rinse, then wash with a piece of white fabric to see if all the bleeding is done.
Although, I really like the idea of putting it in the wash with a bunch of white fabric to add a pale color to it.