//var ids_name ="roll"; var ids_number = 2;
//var rollover = new Array('imagei1','imagei2','imagei3','imagei4');

if (typeof ids_number != 'undefined') {
	var rollover = new Array();
	for (i = 0; i < ids_number; i++) 
	{
    	rollover[i] = ids_name + (i+1);
	}
}

function roll(id,image) {
    var id = document.getElementById(id);
    var image = image;
    id.onmouseover = function () { id.src = id.src.replace("_off.","_on."); }
    if (!id.src.match("_on")) { id.onmouseout = function () { id.src = id.src.replace("_on.","_off."); } }
    id.style.cursor = "pointer";
}

if (typeof rollover != 'undefined') {
	var rollset = new Array(); 
	var preload = new Array()
	var ids = rollover.length;

	for (i = 0; i < ids; i++) 
	{
    	preload[i] = new Image(); 
    	preload[i].src = document.getElementById(rollover[i]).src.replace("_off.", "_on."); 
	}

	for (i = 0; i < ids; i++) 
	{
    	rollset[i] = new roll(rollover[i],preload[i].src);
	}
}