var Roll=new Array();


Roll["contacts"]        = new RollOver("images/contacts_over.jpg");
Roll["home"]        = new RollOver("images/home_over.jpg");



function RollOver(on_url)
{	this.on        = new Image();
	this.on.src    = on_url;
}

function flip ()
{	if(arguments.length==1) arguments[1]=arguments[0];
	for(i=0 ; i<arguments.length ; i+=2){
		temp = document.images[arguments[i]].src;
		document.images[arguments[i]].src  = Roll[arguments[i+1]].on.src;
		Roll[arguments[i+1]].on.src = temp;
	}
}