CTDB in Samba4

[Abhijith Das]

Hi all,
I watched the video of Tridge's talk on ctdb this morning; very cool. 
Kudos to all involved in the effort!
I have a few questions about this clustering effort and I'm hoping I can 
get some answers here.

1. As I understand it, ctdb is being included in Samba4. Is there an 
effort to backport it to Samba3?

2. Are ctdb and tdb inter-changeable as far as samba is concerned? i.e 
can we plug in one or the other into Samba with ease?

3. Transparent failover of samba services: As I'd understood it before, 
transparent failover of a samba service from one node to another was not 
possible without the client reconnecting (as active connections to smbd 
are severed). Does ctdb (or any other current clustering effort) allow 
for transparent failover of samba services across nodes?

Thank you.

Cheers,
--Abhi