function CheckForm(f){
  var eles=new Array("biltitle","bilfname","billname","biladd1","bilcity","bilpostcode","bilcountry","phone","email","password1","password2");
  var msgs=new Array("Please, enter your title","Please, enter your first name","Please, enter your last name","Please, enter your address","Please, enter your town or city","Please, enter postcode","Please, enter your country","Please, enter your phone number","Please, enter your email","Please, enter your password","Please, re-type password");
  for(i=0;i<eles.length;i++){
     if(f.elements[eles[i]].value==''){
        alert(msgs[i]);
        f.elements[eles[i]].focus();
        return false;
     }
  }

  if(f.password1.value!=f.password2.value){
        alert("Password verification error");
        return false;
  }

  return true;
}