// check to see if the specified element is filled
// If it's not, display msg in an alert box and return false;
// else, return true
function checkFilled( elem, msg )
{
   var blankStrRE = /^\s*$/;
   if( blankStrRE.test(elem.value) )
   {
      alert(msg);
      elem.focus();
      return false;
   }
   else {
      return true;
   }
}