//------------------------------------------------------
  function chkEmail(aObj){         
    if (aObj.value.length>0){
      i   = aObj.value.indexOf("@");
      j   = aObj.value.indexOf(".",i);
      k   = aObj.value.indexOf(",");
      kk  = aObj.value.indexOf(" ");
      jj  = aObj.value.lastIndexOf(".")+1;
      len = aObj.value.length;
      if ((i>0) && (j>(i+1)) && (k==-1) && (kk==-1) && (len-jj >=2) && (len-jj<=3))
        return true
      else{
        alert("Please enter an exact email address.\n"+aObj.value + " is invalid.");
        aObj.focus();
        return false;}}
    else{
      alert("Please enter an email address.");
      aObj.focus();
      return false;}}
  //---------------------------------------------------------
  function chkForm(aForm){
    return (chkEmail(aForm.Email));}
  //---------------------------------------------------------