samba - Apr 2008 - Migrate SAMBA 3.0 domain to Windows 2003 AD

Hi Team,
 
If there is any way to migrate from Samba 3.0 domain to windows 2003 AD, please
help me.
 
Please send the procedures how to do this transperently without any changes at
the users side.
There is no roaming profile. All are locally created domain profile.
 
Thanks and Regards,
Shivakumar