function checkContactsForm( form ) {

if (document.RequestForm.first_name.value == ""){
    alert("You must enter a valid first name.");
    document.RequestForm.first_name.focus();
    return false;}

if (document.RequestForm.last_name.value == ""){
    alert("You must enter a valid last name.");
    document.RequestForm.last_name.focus();
    return false;}

return true;
}