function valid()
      {
         var sender_email=document.frm2.sender_email.value;
         var recipient_email=document.frm2.recipient_email.value;
         var message=document.frm2.message.value;

         if(recipient_email.indexOf("@")<1||recipient_email.indexOf(".")<1||recipient_email=='')
            {
               alert("Please, fill in valid Recipient e-mail address.");
               document.frm2.recipient_email.focus();
               return false;
            }
         if(message=="")
            {
               alert("Please enter message");
               document.frm2.message.focus();
               return false;
            }
         return true;
      }