var ns4 = (document.layers) ? true:false;		// Netscape 4.x
var ie = (document.all) ? true:false;			// IE version
var DOM = (document.getElementById) ? true:false;	// DOM supporting versions
var loaded = false;

function init(){	
	var image_names = new Array('nav_designers','nav_departments','nav_featured','nav_about','nav_events','nav_contacts','nav_sitemap');
	if (document.images){		
		images_off  = new Object();
  			images_on   = new Object();			
		for( var x = 0; x < image_names.length; x++ ) {			
       
		images_off[image_names[x]] = new Image();
       	images_off[image_names[x]].src = "images/" + image_names[x] + ".gif";
		
       	images_on[image_names[x]] = new Image();
       	images_on[image_names[x]].src = "images/" + image_names[x] + "_on.gif";

		}			
	}
	loaded = true;			
}		
function rollOn(name) {
    if (loaded) {
		if (ns4) {
			s = document.images[name]; 
    		s.src = images_on[name].src;
    	}
    	else { document.images[name].src = images_on[name].src; }		
	}
}
function rollOff(name) {
    if(loaded) {
    	if(ns4) {
    		s = document.images[name]; 
    		s.src = images_off[name].src;
        }
    	else { document.images[name].src = images_off[name].src; } 		
    }
}