KDE k3b KSycoca error solving

I’ve emerged k3b in my gentoo to be able to write cds from X windows. When trying to fire up k3bsetup I got these strange messages:

root # k3bsetup
_IceTransOpen: Unable to Parse address
Session management error: Could not open network socket
kio (KSycoca): WARNING: Found version 75, expecting version 78 or higher.
kio (KSycoca): WARNING: Outdated database found
kio (KSycoca): ERROR: No database available!
kio (KSycoca): ERROR: No database available!
kio (KSycoca): ERROR: No database available!
kio (KSycoca): ERROR: No database available!
kcmshell (kdelibs): WARNING: Could not find module ‘k3bsetup2’.

I don’t understand what this is. BUT I’ve found a solution to it.
Inside /var/tmp/kdecache-root/ there were 2 files named:

ksycoca ksycocastamp

as soon as you rm them and run k3bsetup again…everything is fine.

It just works…I don’t know what ksycoca is but I’m glad this “solution” works.