I’'ve created a little patch for smack - http://synic.ath.cx/smackchanges.patch.gz that basically removes the requirement for a username and password in the Registration packet.
This way it’‘s more flexible - you can register for things that don’'t need a username and password.
The AccountManager works the same way it did before.
Reading JEP-77 it seems that your modification is correct since no field is required. I quickly looked at your patch and it was difficult to detect the changes since the old classes were completely removed and the new version added. Could you create a patch with only the affected methods? I would love to include your correction.