enableUpdateCallback. Unknown command

if (!isObject(CubeImageSwitcher))
{
   %template = new BehaviorTemplate(CubeImageSwitcher);
   
   %template.friendlyName = "CubeImageSwitcher";
   %template.behaviorType = "PlayerAI";
   %template.description = "Swiches frame of image when cube passes a certain point";
   
   %template.addBehaviorField(image, "image of object being used", object, "", t2dImageMapDataBlock);
   %template.addBehaviorField(frameStart, "frame number image starts with", int, 2);
   %template.addBehaviorField(frameFinish, "frame number image finishes with", int, 1);
   %template.addBehaviorField(switchPointX, "WorldPointX where image must switch frames", float, 75);
}

function CubeImageSwitcher::onBehaviorAdd(%this)
{
		%this.enableUpdateCallback();
}

function CubeImageSwitcher::onUpdate(%this)
{
	if(isObject(%this.image))	
	%this.position = %this.owner.getPosition();
	
	if(%this.position < %this.switchPointX)
	{
		%this.owner.setFrame(%this.frameStart);
	}
	
	if(%this.position > %this.switchPointX)
	{
		%this.owner.setFrame(%this.frameFinish);
	}
}