Kate gives out debug messages on the console from which it is started

This post on the KDE forum explains what it is doing and how to stop it.

http://forum.kde.org/viewtopic.php?f=22&t=93955

Because you did not disable debug-messages.

Open "kdebugdialog", search for "kate" and unselect all checkboxes. Now kate won't talk to you, anymore.