I am experiencing problems migrating from Exchange 2003 to Exchange 2010. I am on the first step: installing a new 2010 Client Access Server role.

The Active Directory domain functional level is 2003. All domain controllers are 2003 R2.

The only existing Exchange 2003 server happens to be housed on one of the domain controllers. It is running Exchange 2003 Standard w/ SP2.

IPv6 is enabled and working on all domain controllers, servers, and routers, including this new Exchange server.

After installing the CAS role on a new 2008 R2 server (Hyper-V VM) I am receiving 2114 Events:

Process MSEXCHANGEADTOPOLOGYSERVICE.EXE (PID=1600). Topology discovery failed, error 0x80040a02 (DSC_E_NO_SUITABLE_CDC). Look up the Lightweight Directory Access Protocol (LDAP) error code specified in the event description. To do this, use Microsoft Knowledge Base article 218185, "Microsoft LDAP Error Codes." Use the information in that article to learn more about the cause and resolution to this error. Use the Ping or PathPing command-line tools to test network connectivity to local domain controllers.

Prior to each, I receive the following 2080 Event:

Process MSEXCHANGEADTOPOLOGYSERVICE.EXE (PID=1600). Exchange Active Directory Provider has discovered the following servers with the following characteristics: 
 (Server name | Roles | Enabled | Reachability | Synchronized | GC capable | PDC | SACL right | Critical Data | Netlogon | OS Version) 
In-site:
b.company.intranet  CDG 1 0 0 1 0 0 0 0 0
s.company.intranet  CDG 1 0 0 1 0 0 0 0 0
 Out-of-site:
a.company.intranet  CD- 1 0 0 0 0 0 0 0 0
o.company.intranet  CD- 1 0 0 0 0 0 0 0 0
g.company.intranet  CD- 1 0 0 0 0 0 0 0 0

Connectivity between the new Exchange server and all domain controllers via IPv4 and IPv6 are all working. I have verified that the new Exchange server is a member of the following groups:

Exchange Servers
Exchange Domain Servers
Exchange Install Domain Servers
Exchange Trusted Subsystem

Heck, I even put the new Exchange server into Domain Admins just to see if it would help. It didn't.

I can't find any evidence of Active Directory replication problems, all pre-setup Setup tasks (/PrepareLegacyExchangePermissions, /PrepareSchema, /PrepareAD, /PrepareDomain) completed successfully. The only problem so far that I haven't been able to resolve with my Active Directory is I am unable to get my IPv6 subnets into Sites and Services

Where should I proceed from here?