function isInteger (s)
{
      var i;

      if (isEmpty(s))
      if (isInteger.arguments.length == 1) return 0;
      else return (isInteger.arguments[1] == true);

      for (i = 0; i < s.length; i++)
      {
         var c = s.charAt(i);

         if (!isDigit(c)) return false;
      }

      return true;
 }
function isEmpty(s)
{
    return ((s == null) || (s.length == 0))
}

function isDigit (c)
{
   return ((c >= "0") && (c <= "9"))
}

/*function isValidEmail(str) 
{
   return (str.indexOf(".") > 2) && (str.indexOf("@") > 0);
 
}*/

function isValidEmail(address) 
{
   var reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
   if(reg.test(address) == false) {
      return false;
   }
   else
   {
	   return true;
   }
}