There is an issue regarding unexplained 'leap second issues' in the current ntp version. 4.2.8p3 and above from upstream fixes this. 4.2.8p3 needs importing then stabilisation. It only contains leap second fixes and an unrelated security fix. Reproducible: Always
This report seems pretty useless by itself; I'm marking it as a dupe. *** This bug has been marked as a duplicate of bug 553682 ***