var	tcRov	=	new	Class({
	initialize : function( groupname  ) {
		var	gname	=	groupname || 'img.rov';
		$$(gname).each(function(img) {
			var src = img.getProperty('src');
			var extension = src.substring(src.lastIndexOf('.'),src.length)
			var down = src.substring(src.lastIndexOf('_'),src.length - extension.length)

			img.setStyle('cursor', 'pointer');

			if( down == '_down' )	{
				img.addEvent('mouseenter', function() { img.setProperty('src',src.replace('_down', '_over' )); });
			}
			else	{
				img.addEvent('mouseenter', function() { img.setProperty('src',src.replace(extension,'_over' + extension)); });
			}
			img.addEvent('mouseleave', function() { img.setProperty('src',src); });
		});
	}
});