This bug has been marked as duplicate of bug #798091, but I'm not so sure they refer to the same issue. Let me explain the issue that is affecting to me in this bug:
Whenever you try to leave the kdm settings in the systemsettings, whether or not you changed anything you receive a warning message that says if you want to apply the changes. Irrespective of whether you say yes or not, this makes that part of your personal configuration changes to some kde or kubuntu default, in my case this refers to the font sizes in the desktop, and the use of text in the toolbars by the default.
This bug has been marked as duplicate of bug #798091, but I'm not so sure they refer to the same issue. Let me explain the issue that is affecting to me in this bug:
Whenever you try to leave the kdm settings in the systemsettings, whether or not you changed anything you receive a warning message that says if you want to apply the changes. Irrespective of whether you say yes or not, this makes that part of your personal configuration changes to some kde or kubuntu default, in my case this refers to the font sizes in the desktop, and the use of text in the toolbars by the default.