We introduced a new logging system in December of 2012. That new system required us to "enhance" each of the site's workouts over to the new format. Unfortunately, because we have so many workouts, we were unable to get to them all. If you ever come across a workout that needs to be upgraded/enhanced email support with the workout ID and they'll get it taken care of for you. If you are using the website, you'll know the workout hasn't been upgraded yet because you'll see the orange "Legacy" icon next to the name of the workout.
You can still log a result for the workout but you'll have to use the old, or "legacy", builder. It won't be as intuitive as the new system, but it'll do until we are able to enhance every workout.