IMO Quakers are like kids cranked up on a sugar rush. Ours is aggressive also until she is out of her cage. It sounds like you either have a tamed breeder or a tamed pet that has gone semi-feral. Try what Lori said and give her some time to gain some trust in you. You may also want to teach her "step up" so she will do it on command. Use it every time you are taking her out of the cage for her free time. Then she should associate it with being able to come out. I say it to our little girl before I get close and she then changes her attitude and watches my finger so she can get on it and not bite it.
Good luck.
