if(document.images){
	
	nav1_off = new Image; nav1_off.src=href="http://www.cred.columbia.edu/test/images/navigation/aboutcred_off.gif";
	nav1_roll = new Image; nav1_roll.src=href="http://www.cred.columbia.edu/test/images/navigation/aboutcred_roll.gif";
	
	nav2_off = new Image; nav2_off.src=href="http://www.cred.columbia.edu/test/images/navigation/research_off.gif";
	nav2_roll = new Image; nav2_roll.src=href="http://www.cred.columbia.edu/test/images/navigation/research_roll.gif";
	
	nav3_off = new Image; nav3_off.src=href="http://www.cred.columbia.edu/test/images/navigation/partnerships_off.gif";
	nav3_roll = new Image; nav3_roll.src=href="http://www.cred.columbia.edu/test/images/navigation/partnerships_roll.gif";
	
	nav4_off = new Image; nav4_off.src=href="http://www.cred.columbia.edu/test/images/navigation/newsevents_off.gif";
	nav4_roll = new Image; nav4_roll.src=href="http://www.cred.columbia.edu/test/images/navigation/newsevents_roll.gif";
	
	nav5_off = new Image; nav5_off.src=href="http://www.cred.columbia.edu/test/images/navigation/decisionpolicymakers_off.gif";
	nav5_roll = new Image; nav5_roll.src=href="http://www.cred.columbia.edu/test/images/navigation/decisionpolicymakers_roll.gif";
	
	nav6_off = new Image; nav6_off.src=href="http://www.cred.columbia.edu/test/images/navigation/studentsteachers_off.gif";
	nav6_roll = new Image; nav6_roll.src=href="http://www.cred.columbia.edu/test/images/navigation/studentsteachers_roll.gif";
	
	}
	
	function chgImg(name,arg){
	   if(document.images){
	     document.images[name].src=eval(arg + ".src");
		 }
	}