samba - Aug 2012 - migration from windows 2003 DC to samba4 DC

hello everyone.

i am Planning migrating my microsoft infrastructure to linux gradually.
i successfully migrated  Fileserver, Virtualization, Proxy. now my
goal is to replace my domain controller holding 2003 server.

i have a mix client (33 clients)  infrastructure including, WindowXP,
2003 Memeber server and Windows 7 while all are memeber of domain with
default GPO, though i wanted to use GPOs in future via samba4,

here is the detail of my domain controller,

1. 2003 Active directory
2. active directory integrated DNS with DNS forwarder.
3. DHCP.


so my questions are.

As per my understanding with DC . i can use ADC for failover.

- is it possible to install samba DC as an ADC and later promoted to DC?

- is there any one has migrated windows DC to SAMBA DC. what was
his/her strategy/experience (any suggestions would be appreciated).

- can anyone please tell me about the stability of SAMBA4. with his
personal experience  , since it is in beta stage?
  because my 2003 DC server is in production and i don't have a clue
that beta is a better way to go in production or not.


my requirement with samba4 after migration are.


1. DC
2. Integrated DNS so that when ever host join's. DNS records and other
updates in AD should be done by it self. (same ad windows  AD)
3. DHCP
4. Group policy implementation.

BTW, i am using 2.7 SAMBA as file sharing server integrated with 2003 AD.
so is it going to effect the migration or not? or samba 2.7 with
consider SAMBA4 machine as an old DC.

Thanks,