IBHA is International Buckskin Horse Association. She can be dual registered AQHA and IBHA if you take photos of all of her dun factoring and send them to IBHA. She'll then be able to show IBHA circuit as well.
Java is registered ABRA (American Buckskin Registry Association), IBHA (International Buckskin Horse Association), AQHA (American Quarter Horse Association) and I'm hoping to get him in the Good as Gold program with PHBA (Palomino Horse Breeders of America).
IBHA and ABRA are a bit pickier about dun coloration than AQHA is. That's why you need to send documentation and photos of all of her dun factoring as well as regular conformation shots. They look at each application coming through and assess whether the horse is considered a dun or not.
Okay, I am not quite sure if she is registered in IBHA, but I will see when we get her papers :) If not, I will try to register her in it.
Thanks for all the info! I will have to research into it, when sending in applications, does it cost money, and do you have to include AQHA papers?