function validate_form()
{
  var email = document.getElementById('email');
  if (validate_email(email,"Not a valid e-mail address!")==false)
    {email.value=""; email.focus(); return false;}
  else {ajaxFunction(); alert("Thank You for subscribing for our news letter!");}
}

function validate_email(field,alerttxt)
{
with (field)
  {
  apos=value.indexOf("@");
  dotpos=value.lastIndexOf(".");
  if (apos<1||dotpos-apos<2)
    {alert(alerttxt);return false;}
  else {return true;}
  }
}

function ajaxFunction(){
        var ajaxRequest;  // The variable that makes Ajax possible!

        try{
        // Opera 8.0+, Firefox, Safari
        ajaxRequest = new XMLHttpRequest();
        } catch (e){
                // Internet Explorer Browsers
                try{
                        ajaxRequest = new ActiveXObject("Msxml2.XMLHTTP");
                } catch (e) {
                        try{
                                ajaxRequest = new ActiveXObject("Microsoft.XMLHTTP");
                            } catch (e){
                                        // Something went wrong
                                        alert("Your browser broke!");
                                        return false;
                                    }
                            }
                }
        // Create a function that will receive data sent from the server
        ajaxRequest.onreadystatechange = function(){
                if(ajaxRequest.readyState == 4){
//                    document.getElementById("res").innerHTML = ajaxRequest.responseText;
		return "ok";
                }
        }
        email_addr = document.getElementById('email').value;
        ajaxRequest.open("GET", "js/send_mail.php?email=" + email_addr, true);
        ajaxRequest.send();
        }