Adding a Fresnel term

I've attempted to add a Fresnel term to the dielectric.

To start, I rendered a sphere with an index of refraction of 1.00, no Fresnel term, no reflections:


Here's another sphere, no reflections, index of refraction 1.33:


Now with a Fresnel term, index of refraction 1.00:



Also with a Fresnel term, index of refraction 1.33:


Those last two images don't look quite right. The reflections are way too strong and are pretty blown out.

I believe that I'm using the equations at http://en.wikipedia.org/wiki/Fresnel_equations to add the Fresnel term.