Unknown Identifier?

I have two scripts added to a camera, one of which is my "GameManager" that keeps track of score, etc.

At the top of this GameManager script, I have variables declared like this:

static var score = 0;

In the other script attached to the camera I am trying to access the score variable through GameManager.score, but it simply shows the error "BCE0005: Unknown identifier: 'GameManager'."

I don't understand how that works because I am accessing that score variable just fine through another script that is attached to another object through GameManager.score... Is it because the GameManager script was added after the first script attached to the camera, or am I doing something else wrong?