essentially, by saying that people with blue eyes have underdeveloped (and therefor somehow defective) eyes, is about as intelligent as saying that white people are underdeveloped and therefor defective because we don't have as much melanin in our skin as black people.
if we further dally down this road of thought, we can come to the INFORMED conclusions that blue eyes and light skin are both the result of evolutionary adaptation to climates with less direct sunlight, and therefor less need for high levels of melanin in the skin. this allows for more absorption of Vitamin D from sunlight, whereas people with high levels of melanin can suffer from Vitamin D deficiency more easily.
both are simply the result of human evolution and are examples of humans adapting to their environments.
wow. getting the facts is really hard. *cough*
(there is a bit more to it, but that's the basics. spend a little time on wikipedia, it will do you good.)