Is not possible - Official suckage documented here KB14202-How to remove an IT policy from a BlackBerry smartphone

Which is bizzare because you can use transporter to migrate users from BES 4<-> Bes 5 domains but not a mixed one. Anyone know if a workaround - apart from upgrade your domain to 5.0 server only?

Thx,
Z

BES 5 added a foreign key field to the database to handle user id mappings from the different domains. This database key is not in a 4.1.x schema. It you try and move a user via ET to a 4.1.x domain there is potential for user_id collisions in the DB.

I Spoke to RIM about this one and the rep was suprised that it didn't work (could'nt work on ticket at the time of callback). Will update if I hear anything different