Version: (using KDE Devel) Installed from: Compiled sources Open konsole, Settings -> edit current profile, change anything, press Default, what you changed does not go to the default value. I guess you should try to use something like kconfigxt that automanages those things.
SVN revision 748994: ""Remove the non-working Defaults button from the Edit Profile dialog. Will be re-instated once there is working code to load and set the defaults."
It seems this bug no longer applies in KDE 4. There is no "Default" button in the Settings->Edit Current Profile dialog.
The default button hasn't been there in a long time. I'm not positive there should be a default button.