samba upgrade question

[Javid Abdul-AJAVID1]

Hi
whats the best way to upgrade samba, am currently running 2.0.7 and would
like to upgrade to 2.2.5, 
the machine account is now moved to secrets.tdb, can i simply move the
existing machine SID to private directory in new version
or i have delete the old one and and rejoin samba again
thanks in advance