Fedora directory users - Nov 2007 - multiple AD servers and password sync

Apologies if this has been covered before somewhere.

I am trying to implement AD <--> FDS syncronization, and don''t
understand what I need to do about setting up the Password Sync on the
AD server when there are (in my case) 3 AD servers.
>From reading the docs, and from my understanding of how windows clients
bind to AD server to change their passwords, it appears that password
sync needs to be installed on every AD server to catch an interactive
password change from a windows client which has bound to any one of 3 AD
servers.

For example:

AD servers are all serving one domain
  AD1 (password sync --> FDS1, sync agreement <--> FDS1)
  AD2 (no password sync)
  AD3 (no password sync)

FDS servers have 1 master/supplier, one replica/consumer
  FDS1 (win sync <--> AD1, supply --> FDS2)
  FDS2

So, if win client talks to a non-passwordsync AD3 and changes password,
then AD3 synchronizes to AD1, then password sync hooks on AD1 can''t
understand the already windows-encrypted password from AD3 because it''s
not part of the initial interactive password change.  If that''s true,
then I definitely have to have Password Sync on every AD server, along
with the certs etc etc.  Is this the case?

A collateral question is: what happens if you have 3 AD servers with
sync agreements to an FDS server?  Will you get 3 updates to FDS on the
same user change?  Will FDS updates sent to all 3 AD servers result in
trouble as the AD servers subsequently sync to each other?


- Aaron