If you manage to get your hands on the painted shirt before the paint dries, paint thinner works great (my husband's a painter). The paint thinner won't damage the clothes (At least not cotton clothes. We've never tried it on rayon or silk). After the paint dries, it binds to the fabric - the way paint does to walls - and won't come out.

A homemaking mom helping writers on the internet. www.powerpenmarketsearch.com