//Active Images for rollover images
 
  env_topnav_header = new Image();
  env_topnav_header.src = "images/env_topnav_header.gif";
  env_topnav_header.on = new Image();
  env_topnav_header.on.src = "images/env_topnav_header.on.gif";
 
  env_topnav_about = new Image();
  env_topnav_about.src = "images/env_topnav_about.gif";
  env_topnav_about.on = new Image();
  env_topnav_about.on.src = "images/env_topnav_about.on.gif";
 
  env_topnav_mission = new Image();
  env_topnav_mission.src = "images/env_topnav_mission.gif";
  env_topnav_mission.on = new Image();
  env_topnav_mission.on.src = "images/env_topnav_mission.on.gif";
 
  env_topnav_services = new Image();
  env_topnav_services.src = "images/env_topnav_services.gif";
  env_topnav_services.on = new Image();
  env_topnav_services.on.src = "images/env_topnav_services.on.gif";
 
  env_topnav_projects = new Image();
  env_topnav_projects.src = "images/env_topnav_projects.gif";
  env_topnav_projects.on = new Image();
  env_topnav_projects.on.src = "images/env_topnav_projects.on.gif";
 
  env_topnav_contact = new Image();
  env_topnav_contact.src = "images/env_topnav_contact.gif";
  env_topnav_contact.on = new Image();
  env_topnav_contact.on.src = "images/env_topnav_contact.on.gif";
 
  env_topnav_docs = new Image();
  env_topnav_docs.src = "images/env_topnav_docs.gif";
  env_topnav_docs.on = new Image();
  env_topnav_docs.on.src = "images/env_topnav_docs.on.gif";
 
  env_topnav_links = new Image();
  env_topnav_links.src = "images/env_topnav_links.gif";
  env_topnav_links.on = new Image();
  env_topnav_links.on.src = "images/env_topnav_links.on.gif";

//Code for image rollovers for IE4+
function changeImages() {
	if (document.images) {
    	for (var i=0; i<changeImages.arguments.length; i+=3) {
    	document[changeImages.arguments[i]].src = eval(changeImages.arguments[i+1] + ".src");
    	}
	} 
}

function button_swap(imagename,objectsrc) {
	document.images[imagename].src=eval(objectsrc+".src")
}