Can you at least mention a complete login and logout procedure in general, as nearly all information to reproduce this is missing.
E.g. you login as your user, start some applications, then switch to your wife's user account via K-Menu -> Leave ... -> Switch user (which starts a new X server and a new session), a different set of applications is started. Then you logout with both users, and login again. As you started a new session for your wife's user, session handling will be affected. If you login again, and switch to your wife's user via K-Menu -> Leave ... -> Switch user (or on the screensaver/lock screen, which does the exact same thing, start a new session, which will obiously not restore the last saved session) you will start a new session, so old session will not be restored. From what I can see, this is normal behaviour, there's just some wrong expectations on your side.
What do you do, how exactly and what does it result in and what's the expected result?
Maybe what you need is
http://kde-look.org/content/show.php?content=127462 - I'm currently rebuilding the OpenSUSE package for Mageia and will try it out.
You should probably ask upstream in KDE forums how this is supposed to work and how you can achieve what you want.
Related information I've found:
http://forum.kde.org/viewtopic.php?f=66&t=52608http://forums.opensuse.org/english/get- ... login.html and
http://forums.opensuse.org/english/othe ... sions.html