Unity iPhone is currently based on Unity 2.1, which (being an earlier version) doesn't have the same editor scripting functionality. Unity 3 is a unified editor so that's not an issue any more after it's released.
Actually, it looks like the IPhone version is just a bit more persnickety, and I didn't notice a build warning. Fixed that, and 2.6 IS scriptable after all. Sorry for false alarm.