// JavaScript Document

	function findimg()
	{
		var i;
		var imgs = document.getElementsByTagName('img');
		
		// loop through all images of the document
		
		for( i=0; i<imgs.length; i++)
		{
			// test if the class 'roll' exists
			
			if(/roll/.test(imgs[i].className))
			{
				// add the function roll to the image onmouseover and onmouseout and send
				// the image itself as an object
				
				imgs[i].onmouseover=function(){roll(this);};
				imgs[i].onmouseout=function(){roll(this);};
			}
		}
	}
	function roll(o)
	{
		// get the src of the image, and find out the file extension
		
		var src = o.src;
		var ftype = src.substring(src.lastIndexOf('.'), src.length);
		
		// check if the src already has an _on and delete it, if that is the case 
		
		if(/-over/.test(src))
		{
			var newsrc = src.replace('-over','');
		}
		else
		{
			// else, add the _on to the src 
			var newsrc = src.replace(ftype, '-over' + ftype);
		}
		
		o.src=newsrc;
	}
	
	window.onload=function()
	{
		findimg();
	}