function trim(cadena)
{
	for(i=0; i<cadena.length; )
	{
		if(cadena.charAt(i)==" ")
			cadena = cadena.substring(i+1, cadena.length);
		else
			break;
	}
	for(i = cadena.length-1; i>=0; i = cadena.length-1)
	{
		if(cadena.charAt(i)==" ")
			cadena = cadena.substring(0,i);
		else
			break;
	}
	return cadena;
}

function getCookie(name){
  var cname = name + "=";               
  var dc = document.cookie;             
  if (dc.length > 0) {              
    begin = dc.indexOf(cname);       
    if (begin != -1) {           
      begin += cname.length;       
      end = dc.indexOf(";", begin);
      if (end == -1) end = dc.length;
        return unescape(dc.substring(begin, end));
    } 
  }
  return null;
}

function setCookie(name, value, expires, path, domain, secure) {
  document.cookie = name + "=" + escape(value) + 
  ((expires == null) ? "" : "; expires=" + expires.toString()) +
  ((path == null) ? "" : "; path=" + path) +
  ((domain == null) ? "" : "; domain=" + domain) +
  ((secure == null) ? "" : "; secure");
}

function delCookie(name,path,domain) {
  if (getCookie(name)) {
    document.cookie = name + "=" +
    ((path == null) ? "" : "; path=" + path) +
    ((domain == null) ? "" : "; domain=" + domain) +
    "; expires=Thu, 01-Jan-70 00:00:01 GMT";
  }
}