B&N has added some kind of check to block apps with certificates that were not from them. we had this upgrade issue in 1.2 as well initially.
We fixed it by replacing a class file in services.jar ( one of the system jar files) with the one from 1.1 version. I forgot which one and nobody seems to remember it now
Someone has to go thro' the classes and figure out which one again. I'll try to do it next weekend if it's not done by then.