Rotation glitch with camera

So I took the SmoothFollow script for my camera, which works pretty well, and wanted to add some kind of Roll (Z rotation) to the camera when it turns to make it more dynamic.

Most of the time my script works well except at a certain angle where it jumps and turns suddenly to ridiculously high values (like 180 when usually I get angles between 15 and -15). I fixed that by limiting the angles to 15 max both ways but it still jumps to 15 and makes it feel a bit awkward. I suspect this angle is the transition between 360 and 0 but I have no idea how to fix that. Here's the script :

 var target : Transform;
 // The distance in the x-z plane to the target
 var distance = 10.0;
 // the height we want the camera to be above the target
 var height = 5.0;
 // How much we 
 var heightDamping = 2.0;
 var rotationDamping = 3.0;
 var cameraRoll : float;
 
 // Place the script in the Camera-Control group in the component menu
 @script AddComponentMenu("Camera-Control/Smooth Follow")
 
 
 function LateUpdate () {
     
     
     var newheight = height + Input.GetAxis( "Mouse Y" );
     // Early out if we don't have a target
     if (!target)
         return;
     
     // Calculate the current rotation angles
     var wantedRotationAngle = target.eulerAngles.y;
     var wantedHeight = target.position.y + height;
         
     var currentRotationAngle = transform.eulerAngles.y;
     var currentHeight = transform.position.y;
     
     // Damp the rotation around the y-axis
     currentRotationAngle = Mathf.LerpAngle (currentRotationAngle, wantedRotationAngle, rotationDamping * Time.deltaTime);
     
     // Damp the height
     currentHeight = Mathf.Lerp (currentHeight, wantedHeight, heightDamping * Time.deltaTime);
     
     // Convert the angle into a rotation
     var currentRotation = Quaternion.Euler (0, currentRotationAngle, 0);
     
     // Set the position of the camera on the x-z plane to:
     // distance meters behind the target
     transform.position = target.position;
     transform.position -= currentRotation * Vector3.forward * distance;
 
     // Set the height of the camera
     transform.position.y = currentHeight;
     
     // Always look at the target
     transform.LookAt (target);
     
     var beforeRoll = (wantedRotationAngle - currentRotationAngle)/3; // Takes the values of the camera turning and attenuate them
     
     if(beforeRoll < 15 && beforeRoll > -15 && beforeRoll != 0){ 
         cameraRoll = beforeRoll; // Prevents the angles to go over 15 both way
     }
     
     transform.eulerAngles.z = cameraRoll; // Applies the angle
 }

Does anyone got any idea what to do?