[CentOS] Single sign-on for CentOS-6

Does anyone here use a Samba4 setup for single sign-on for MS_Win workstations
and CentOS-6 boxes?   Does anyone here use it for imap and/or smtp
authentication?   We are experimenting with replacing our existing Microsoft
domain controllers with Samba4 based controllers and are contemplating moving
all authentication for all our systems, Microsoft and CentOS based, over to
Samba when, or if, this replacement successfully completes.

Does anyone have any references for using CentOS with Samba domain controllers
that they can recommend?  I have found some but the few I have found tend to
be Samba3 specific.

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James B. Byrne                mailto:ByrneJB at Harte-Lyne.ca
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