In addition to the problem to install this Beta version, read this, BigBoss warns you on the installation of Fimware 4.0 beta for several reasons :
- It is a Beta version, then if you are not a Developer, you will NOT be able to install it without a Developer account.
- End of Beta version : June 2nd 2010
- Your baseband will change to version 05.13 then if you want to keep your unlock, keep away from this Firmware 4.0
- Beta version slow and not stable.
- Moreover, to resotre an old Firmware, if you don't have your ECID file, you will have troubles...