// name - name of the cookie
// value - value of the cookie
// [expires] - expiration date of the cookie (defaults to end of current session)
// [path] - path for which the cookie is valid (defaults to path of calling document)
// [domain] - domain for which the cookie is valid (defaults to domain of calling document)
// [secure] - Boolean value indicating if the cookie transmission requires a secure transmission
// an argument defaults when it is assigned null as a placeholder
// a null placeholder is not required for trailing omitted arguments
function setCookie(name, value, expires, path, domain, secure) 
{
  document.cookie = name + "=" + escape(value) 
  	+ ((expires) ? "; expires=" + expires.toGMTString() : "") 
	+ ((path) ? "; path=" + path : "") 
	+ ((domain) ? "; domain=" + domain : "") 
	+ ((secure) ? "; secure" : "");
}

// name - name of the desired cookie
// return string containing value of specified cookie or null if cookie does not exist
function getCookie(name) 
{
  var dc = document.cookie;
  var prefix = name + "=";
  var begin = dc.indexOf("; " + prefix);
  if (begin == -1) 
  {
    begin = dc.indexOf(prefix);
    if (begin != 0) return null;
  }
  else
    begin += 2;
  var end = document.cookie.indexOf(";", begin);
  if (end == -1) end = dc.length;
  return unescape(dc.substring(begin + prefix.length, end));
}

// name - name of the cookie
// [path] - path of the cookie (must be same as path used to create cookie)
// [domain] - domain of the cookie (must be same as domain used to create cookie)
// path and domain default if assigned null or omitted if no explicit argument proceeds
function deleteCookie(name, path, domain) 
{
  if (getCookie(name)) 
  {
	var nowMinOneYeay = new Date();
	fixDate(nowMinOneYeay); // fix the bug in Navigator 2.0, Macintosh
	nowMinOneYeay.setYear(nowMinOneYeay.getYear()-1);
	setCookie(name,  "", nowMinOneYeay, path, domain);
  }
}

// date - any instance of the Date object
// hand all instances of the Date object to this function for "repairs"
function fixDate(date) 
{
  var base = new Date(0);
  var skew = base.getTime();
  if(skew > 0) date.setTime(date.getTime() - skew);
}