function numbersOnly(myfield, e, dec) {
 var key; var keychar;
 if (window.event) key = window.event.keyCode;
 else if (e) key = e.which;
 else return true;
 keychar = String.fromCharCode(key);
 // control keys
 if ((key==null) || (key==0) || (key==8) || (key==9) || (key==13) || (key==27)) return true;
 // numbers
 else if ((("0123456789").indexOf(keychar) > -1)) return true;
 // decimal point jump
 else if (dec && (keychar == "."))
 {
 myfield.form.elements[dec].focus();
 return false;
 }
 else return false;
}