Nein.
SSO bedeutet in diesem, dass sich der User nicht per HTTP authentifiziert sondern via Notes. Dazu muss 1352 auf dem Sametime Server offen sein.
Mit dem Internetpasswort hat das rein gar nix zu tun.
Rein sicherheitstechnisch ist das der sicherere Weg.
Hier die Technote:
How Does the Notes Instant Messaging Preference for Logging on via SSO Work?
Technote (FAQ)
Problem
In Notes 6.5.x, there is a user preference on the Instant Messaging/General tab to "Log on to IBM Lotus Instant Messaging using Single Sign-On (SSO)." How does this preference work?
Solution
When the Lotus instant messaging (Sametime) server is configured for multi-server SSO, the user preference enables users to log onto Notes instant messaging using the Notes logon and avoid having to log in separately using the Internet password that is specified in the person document in the Domino Directory.
How it works:
The user authenticates in Notes by logging in via the Notes user name and password. This identity is then used by an authenticated NRPC transaction (like any other authenticated NRPC transaction) to securely request an LTPA token from the Sametime server. The token is then used to log the user into Notes instant messaging over the Sametime protocol.
The Notes NRPC port (1352) must be open on the Sametime server for the login via SSO to work.
A few points of clarification with respect to passwords:
To make use of the user preference and log in to Notes instant messaging via SSO, it is not necessary for users' Internet passwords to be the same as their Notes passwords. In fact, when users log in to Notes instant messaging via SSO, the Internet password is not used; even if the Internet password field is blank, users will be able to log on to Notes instant messaging via SSO.
For information on configuring multi-server SSO, refer to the Lotus Domino 6.5.x Administrator's Guide.