var myrules = {
		'img.img_rollover' : function(element)
		{	
			// preload the rollover image
	//		preload(element);
			
			// onmouse over handler
			element.onmouseover = function()
			{
				rollover(this);		
			}
			
			// onmouse out handler
			element.onmouseout = function()
			{
				rollover(this);
			}			
						
		}
	};
	
	Behaviour.register(myrules);