This is actually done, and there is a small amount of evidence that the orb might still work to some extent.
Geronimo needs to extend an impl class, so rev 932189 exports it. Maybe there's a better way to make this happen, perhaps a fragment bundle or moving the yoko class.
rev 934301 gets classloading to work in osgi using code cribbed from Ricks work on the specs Service locating. This code should mostly be in a separate bundle.
rev 934468 moves the locator code to its own bundle
rev 936530. Give the BundleProviderLoader a priority to make it easier to predict what class you'll get.
I have been told that there's a good chance that if we don't let the framework export corba and rmi classes, we don't need to put ours in the endorsed directory. We should try this and see if it works.