function validateEmail() {
  var str1 = document.form1.recipt_email.value;
  var str2 = document.form1.sender_email.value;
  var isEmail1 = ((str1.indexOf("@") != -1) && (str1.indexOf(".") != -1));
  var isEmail2 = ((str2.indexOf("@") != -1) && (str2.indexOf(".") != -1));
  var formfield = document.form1 
  
  if (formfield.recipt_name.value.length == 0) {
    alert("Please enter the Recipient's Name:.");
    formfield.recipt_name.focus();
    return false;
  }
  if (!isEmail1) {
    alert("Sorry, that is an invalid email address!");
    formfield.recipt_email.select();
    formfield.recipt_email.focus();
    return false;  
  }  
  if (formfield.sender_name.value.length == 0) {
    alert("Please enter the senders name.");
    formfield.sender_name.focus();
    return false;
  }
  if (!isEmail2) {
    alert("Sorry, that is an invalid email address!");
    formfield.sender_email.select();
    formfield.sender_email.focus();
    return false;  
  } 
}