<!-- Hide script from old browsers
/* Initial id in global var */ 
var currId = 'div_1'; 
// 
function show_div(div_id) {  
    if(currId) 
    	document.getElementById(currId).style.display = 'none'; 
    document.getElementById(div_id).style.display = 'block'; 
    currId = div_id; 
} 
// End hiding script from old browsers -->