"Clock skew too great" but clocks synchronized?

[Christian Huldt]

A short time ago I stopped being able to login to a samba 3.6.3 member server on a domain a samba4 beta8 dc ,
kinit on he member reported "Clock skew too great" but the time was on 4 seconds off, and even after synchronizing the clocks I still get the same message.
date -u and date are the same on both machines.

I just don't understand it at all. Please, could some one think of anything?