https://bugzilla.redhat.com/show_bug.cgi?id=1120404
--- Comment #5 from markm marek78uk@o2.pl --- (In reply to Christopher Meng from comment #3)
Well....
If you get this problem by upgrading the kernel, you should fill a bug against kernel first.
I wasn't sure... and decided to put it against docky - glad was pointed in the right direction! Many thanks!