The CBJUICE package has been completely rewritten to use the CBAPI. It will support multiple usertypes/groups in Joomla 1.6 with CB version 1.4
The new release of CBJUICE has been patched to correctly handle a default usertype on ADD in 1.5.22. The release can be found on
joomlacode.org/gf/project/cbjuice/
More recent releases include support for 1.7. Please always use the latest version if you are on Joomla 1.6/7