I tryed some fancy stuff to point /etc/localtime to ../usr/share/zoneinfo/Europe/Amsterdam. The clock script didn't like this relative path and broke the boot. I suggest a fix where it checks if the file exists instead of 'just' die.
works just fine hwclock shouldnt care ... as long as the symlink isnt broken, it doesnt matter if it's relative or absolute running this: file -L /etc/localtime should tell you whether the link is correct