[eluser]Pascal Kriete[/eluser]
I can't reproduce, but I also had to remove the db specific stuff. Let's go back another step and start with something even simpler.
I've attached a zip of a basic controller and view, with only one required field. My test setup (php 4.4.7) is autoloading the validation library. Can you try running that very simple controller and tell us what errors, if any, come up.
Once we get that up to speed we can start reconstructing your original code.