ใช้ javascript 2 อันแล้วมีปัญหาค่ะ มันขึ้นแค่อันเดียว

	<script src="jquery-1.10.1.js"></script>
<script>
	function same(checker1,checker2){
		if(checker1 == checker2){
			alert('ชื่อผู้ทบทวนโครงร่างซ้ำ!!! กรุณาเลือกใหม่ค่ะ');
			return false;	
		}
	}
</script>  
	<script type="text/javascript">
		window.addEvent('domready', function() {
		 
			//new vlaDatePicker('exampleI');
			//new vlaDatePicker('exampleII', { separator: '-', leadingZero: false, twoDigitYear: true, offset: { y: 3 }, alignX: 'center', alignY: 'bottom' });
			new vlaDatePicker('exampleII', { openWith: 'togglePicker1', offset: { y: -2, x: 2 }, separateInput: { day: 'protocol_date_day', month: 'protocol_date_month', year: 'protocol_date_year' } });			
			
			new vlaDatePicker('exampleIII', { openWith: 'togglePicker2', offset: { y: -2, x: 2 }, separateInput: { day: 'study_start_date_day', month: 'study_start_date_month', year: 'study_start_date_year' } });
			
			new vlaDatePicker('exampleIIII', { openWith: 'togglePicker3', offset: { y: -2, x: 2 }, separateInput: { day: 'study_end_date_day', month: 'study_end_date_month', year: 'study_end_date_year' } });
			
						new vlaDatePicker('example0', { openWith: 'togglePicker0', offset: { y: -2, x: 2 }, separateInput: { day: 'datewant_sdate_day', month: 'datewant_sdate_month', year: 'datewant_sdate_year' } });
						
									new vlaDatePicker('example00', { openWith: 'togglePicker00', offset: { y: -2, x: 2 }, separateInput: { day: 'datewant_edate_day', month: 'datewant_edate_month', year: 'datewant_edate_year' } });
			
		//	new vlaDatePicker('exampleIV-A', { style: 'adobe_cs3', offset: { y: 1 }, format: 'm/d/y', ieTransitionColor: '' }); 
		//	new vlaDatePicker('exampleIV-B', { style: 'apple_widget', offset: { x: 3, y: 1 } });
		//	new vlaCalendar('exampleV', { startMonday: true });
		//	new vlaDatePicker('exampleVI', { defaultView: 'year' });
		//	new vlaDatePicker('exampleVII', { prefillDate: { day: 12, month: 12, year: 2012 } });			
		});	
	</script>

            <td><select name="checker1" id="checker1" onchange="same($(this).val(),$('#checker2').val());">
			<option value=""><-- กรุณาเลือก --></option>
			<?
			$strSQL = "SELECT * FROM etc_checker ORDER BY id ASC";
			$objQuery = mysql_query($strSQL);
			mysql_query("SET NAMES UTF8");
			while($checker1 = mysql_fetch_array($objQuery))
			{
			?>
			<option value="<?=$checker1["names"];?>"><?=$checker1['id']." - ".$checker1['names'];?></option>
			<?
			}
			?>
		  </select>
                    &nbsp;&nbsp;ผู้ทบทวนโครงร่าง2&nbsp;&nbsp;
          <select name="checker2" id="checker2" onchange="same($(this).val(),$('#checker1').val());">
                    <option value=""><-- กรุณาเลือก --></option>
                    <?
			$strSQL = "SELECT * FROM etc_checker ORDER BY id ASC";
			$objQuery = mysql_query($strSQL);
			mysql_query("SET NAMES UTF8"); 
			while($checker2 = mysql_fetch_array($objQuery))
			{
			?>
                    <option value="<?=$checker2["names"];?>"><?=$checker2["id"]." - ".$checker2["names"];?></option>
            <?
			}
			?>
           </select>
           
    </td>

        <td><span id="exampleII">
					<input name="protocol_date_day" type="text" style="width: 18px; border-width: 1px 0 1px 1px;" maxlength="2" /><input value="/" type="text" style="width: 5px; border-width: 1px 0 1px 0;" disabled="disabled" /><input name="protocol_date_month" class="textbox" type="text" style="width: 16px; border-width: 1px 0 1px 0;" maxlength="2" /><input value="/" type="text" style="width: 5px; border-width: 1px 0 1px 0;" disabled="disabled" /><input name="protocol_date_year" type="text" style="width: 28px; border-width: 1px 0 1px 0;" maxlength="4" /><input type="text" style="width: 15px; border-width: 1px 1px 1px 0;" disabled="disabled" /><img src="images/calendar.gif" id="togglePicker1" class="pickerImg" width="13px" height="12px" alt="" />				</span>	                  </td>