I can confirm the bug in Kubuntu 13.04, where the upgrade from 12.10 overwrote the file
/etc/xdg/autostart/gnome-keyring-pkcs11.desktop
in which I had previously applied a fix as the one described by RichardNeill, i.e. appending "KDE;" to the line "OnlyShowIn=GNOME;Unity;MATE;"
I can confirm the bug in Kubuntu 13.04, where the upgrade from 12.10 overwrote the file
/etc/xdg/ autostart/ gnome-keyring- pkcs11. desktop
in which I had previously applied a fix as the one described by RichardNeill, i.e. appending "KDE;" to the line "OnlyShowIn= GNOME;Unity; MATE;"