// how to use
//       var expdate = new Date ();
//       expdate.setTime (expdate.getTime() + (1000 * 60 * 60 * 24 * 31));
//       setCookie ("_name", "Bob", expdate);
//       document.write(getCookie("_name"));


function setCookie (name, value, expires) {
    a=getCookie(name);
    if (a!=null) {
    	delCookie(name);
//alert("set cookie:"+name+" to:"+value);
    	}    
    if (!expires) expires = new Date();
    //alert("cookie:"+expires.toGMTString());
    document.cookie = name + "=" + escape (value) +  "; expires=" + expires.toGMTString() +  "; path=/"; 
    }       
    
function getCookie (name) {
    var dcookie = document.cookie; 
    var cname = name + "=";
    var clen = dcookie.length;
    var cbegin = 0;
//alert("get cookie:"+name +"    <"+dcookie);
    while (cbegin < clen) {
        var vbegin = cbegin + cname.length;
        if (dcookie.substring(cbegin, vbegin) == cname) { 
            var vend = dcookie.indexOf (";", vbegin);
            if (vend == -1) vend = clen;
           a = unescape(dcookie.substring(vbegin, vend));
 //alert ("cookie found:"+vbegin+":"+vend+":"+a);
           return a;
            }
        cbegin = dcookie.indexOf(" ", cbegin) + 1;
        if (cbegin == 0) break;
        }
//alert("done get");
    return null;
    }

function delCookie (name) {
	a=getCookie(name);
	if (a!=null) {
    	var expireNow = new Date();
    	document.cookie = name + "=" + "; expires=Thu, 01-Jan-70 00:00:01 GMT" +  "; path=/";
    }
    }