function isFilled(elm)
 {
  if (elm.value.length == 0) return false;
  else return true;
 }

function isReady(form) 
 {
  if (isFilled(form.subject) == false) 
  { 
   alert("Please enter a subject for your message.");
   form.subject.focus();
   return false;
  }
  if (isFilled(form.name) == false) 
  { 
   alert("Please enter your name.");
   form.name.focus();
   return false;
  }
  if (isFilled(form.email) == false) 
  { 
   alert("Please enter a valid e-mail address where you can be reached.");
   form.email.focus();
   return false;
  }

  if (isFilled(form.message) == false) 
  { 
   alert("Please enter a message.");
   form.message.focus();
   return false;
  }
}