จะเขียนฟังก์ชั่นยังไง ไม่ให้เลือกเวลาเริ่มต้นและสิ้นสุดทับซ้อน(เวลาเดียวกัน)

<link rel="stylesheet" href="{$set.root_path}includes/share/jquery/datePicker/datePicker.css" />
<script language="javascript" src="{$set.root_path}includes/share/jquery/datePicker/jquery.datePicker.js"></script>
<script type="text/javascript" src="{$set.root_path}includes/share/jquery/datePicker/date.js"></script>
{literal}
<script>
Date.firstDayOfWeek = 0;
Date.format = 'yyyy-mm-dd';
$(function(){
	/*
	$('.date-pick').datePicker({clickInput:true,createButton:false,startDate: '1910-01-01',endDate: (new Date()).asString()});
	*/
	var no = 2;
    $('#add_row').click(function(){
		
         var tr = $('<tbody  id="tr_'+no+'"><tr></tr></tbody>');
         var td1 = $('<td><input type="text" name="eventDate[]" value="" class="input date-pick" maxlength="10" style="width:135px;" /></td>');
         var td2 = $('<td><select name="s_hour[]" style="width:55px;">{/literal}{$data_hour}{literal}</select> <select name="s_minute[]" style="width:55px;">{/literal}{$data_minute}{literal}</select></td>');
         var td3 = $('<td><select name="e_hour[]" style="width:55px;">{/literal}{$data_hour}{literal}</select> <select name="e_minute[]" style="width:55px;">{/literal}{$data_minute}{literal}</select></td>');
		 var td4 = $('<td><img src="{/literal}{$set.theme_images_path}{literal}icons/delete.png" border="0" onclick="javascript:DeleteDataRows(\'tr_'+no+'\');" style="cursor:pointer;" /></td>');
         
         tr.append(td1);
         tr.append(td2);
         tr.append(td3);
		 tr.append(td4);
         
         $('#tbl_order').append(tr);
		 $('.date-pick').datePicker({clickInput:true,createButton:false,startDate:'2000-01-01'});
		 no++;
    }) ;
	$('.date-pick').datePicker({clickInput:true,createButton:false,startDate:'2000-01-01'});

}) ;

function DeleteDataRows(fn_value){
	var targetID = "#"+fn_value;
	$(targetID).fadeOut();
}

function confSend(formID,txtSuccess)
{
	var v2 = $('#eventDate1').val();
	if(v2==""){
		alertMessage(1, '{/literal}{$lang.tutor_courses.tb_schedule_event_date}{literal}', '#eventDate1');
	} else {
		return true;	
	}
	return false;
}
</script>
{/literal}
<div class="inline-middle"><img src="{$set.theme_images_path}icons/persons.png" /></div> <div id="m-title" class="inline-middle">{$lang.tutor_courses.add_schedule}</div>
{if $message!=""}<div id="message-response">{$message}</div>{/if}
<div id="m-content">
<form id="form1" name="form1" action="" method="post" onsubmit="return confSend('form1','{$lang.js.your_information_has_been_added}')" autocomplete="off">
<div style="text-align:right; padding:0 5px 5px;"><a href="#" id="add_row" style="text-decoration:none;"><img src="{$set.theme_images_path}icons/insert.png" border="0" /> Insert Rows</a> </div>
<table width="700" cellpadding="0" class="form" id="tbl_order">
  <thead>
  <tr>
  <th width="200">{$lang.tutor_courses.tb_schedule_event_date}<input type="hidden" name="classID" value="{$classID}" /></th>
  <th width="200">{$lang.tutor_courses.tb_schedule_event_time_start}</th>
  <th width="200">{$lang.tutor_courses.tb_schedule_event_time_end}</th>
  <th width="100">{$lang.tutor_courses.tb_action}</th></tr>
  </thead>
  <tbody>
  <tr>
  <td><input type="text" name="eventDate[]" value="" class="input date-pick" id="eventDate1" maxlength="10" style="width:135px;" /></td>
  <td><select name="s_hour[]" style="width:55px;">{$data_hour}</select> <select name="s_minute[]" style="width:55px;">{$data_minute}</select></td>
  <td><select name="e_hour[]" style="width:55px;">{$data_hour}</select> <select name="e_minute[]" style="width:55px;">{$data_minute}</select></td>
  <td>&nbsp;</td>
  </tr>
  </tbody>
</table>
<input type="submit" value="{$lang.form.add}" class="button-primary" />
</form>
</div>