function valid()
      {
         var sender_name=document.frm2.sender_name.value;
         var email=document.frm2.sender_email.value;
         var subject=document.frm2.subject.value;
         var message=document.frm2.message.value;

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