One example is bug 699400: hwclock is never set correctly when NTP is used (unless it was almost correct before...).
I reported the bug, I argued with the maintainer, it did lead to nothing, the bug was "RESOLVED INVALID" (interesting notion: either it is resolved or it is invalid, then there is nothing to resolve...)
What's my workaround? I exploit the fact that old SysV init uses bash scripts. The init script which sets the clock does source /etc/sysconfig/clock. Internally, it uses a variable ELEVENMIN_MODE.
So what did I do? Simply add
readonly ELEVENMIN_MODE=noat the end of /etc/sysconfig/clock.
The script will throw some errors on boot and shutdown due to its inability to change a readonly shell variable, but I can live much better with a harmless warning than with a totally wrong system time at each reboot :-)
Update: Werner has pointed out in the bug that this is totally wrong and will make a mess of your time settings, so use this at your own risk. OTOH I have more than 2000 productive systems here running with this. We had lots of problems before and have no problems anymore after doing it like described here. So at least for me the wrong solution works good.