In IE, select the onchange event failure

project site there is a strange question , select the onchange event fails, can not trigger an event , but if the change will be able to trigger the onChange , do not know what the reasons are , hope you peer help, thank you ! ~
two machines in the field of IE7 and IE8, will be such a phenomenon, but in the local development environment but can not reproduce .

select is added dynamically on js dynamically add code :

  function newEvent(index){
  	newEventIndex=index+1;
  	return "<tr height=23><td style=\"text-align:center;\"><input type=\"checkbox\" name=\"eventCheck\"/>" +
  				"<input name=\"eventList["+index+"].profileId\" value=\""+profileId+"\" type=\"hidden\"/>"+
  				"<input name=\"eventList["+index+"].eventId\" value=\"\" type=\"hidden\"/>"+
  			"</td>"+
  			"<td style=\"text-align:center;\"><input name=\"eventList["+index+"].produce\" value=\"true\" type=\"checkbox\"/></td>"+
  			"<td style=\"text-align:center;\"><input name=\"eventList["+index+"].eventName\" type=\"text\" size=\"10\" value=\"<s:text name='scriptmonitor.js.tolerantEvent'/>"+newEventIndex+"\"/></td>"+
  			"<td style=\"text-align:center;\"><select name=\"eventList["+index+"].lvel\">"+
  				<s:iterator value="levels" >
  					"<option value=\"${key}\">${value}</option>"+
  				</s:iterator>
  			"</select></td>"+
  			"<td style=\"text-align:center;\"><select name=\"eventList["+index+"].priority\">"+
  				<s:iterator value="prioritys" >
  					"<option value=\"${key}\">${value}</option>"+
  				</s:iterator>
  			"</select></td>"+
  			"<td style=\"text-align:center;\">"+
  				"<span><select name=\"eventList["+index+"].metricId\" style=\"width:80px\" onchange='selectCondition("+index+")' id='condition"+index+"'>"
  				+"<option value='-1'><s:text name='scriptmonitor.js.pleaseChoose'/></option>"+
  				<s:iterator value="scriptMetricList" >
  					"<option value=\"${metricId}\" jsName=\"${dataType}\">${metricName}</option>"+
  				</s:iterator>
  				"</select></span>"+
  				"<span id=\"relationSpan"+index+"\" style=\"padding-left:4px;\"><select id=\"operateModeId"+index+"\" name=\"eventList["+index+"].operateMode\" style=\"width:60px;\" validate=\"select-one\"/></span>"+
  				"<span id=\"synSpan"+index+"\" style=\"padding-left:2px;\"><input id=\"thresholdText"+index+"\" type=\"text\" name=\"eventList["+index+"].threshold\" size=\"12\"/></span>"+
  			"</td>"+
  			"<td style=\"text-align:center;\"><select name=\"eventList["+index+"].produceMode\" validate=\"select-one\">"+
  				<s:iterator value="produceRules">
  					"<option value=\"${key}\">${value}</option>"+
  				</s:iterator>
  			"</select></td>"+
  			"<td style=\"text-align:center;\"><input name=\"eventList["+index+"].alarm\" value=\"true\" type=\"checkbox\"/></td></tr>";
  }
  

generated after html:

  <select name="eventList[0].metricId" id="condition0" style="width: 80px;" onchange="selectCondition(0)" jQuery1382682857232="379">
  

------ Solution ------------------------------------- -------
seems to have browser compatibility problems , I hope to help you.
http://blog.csdn.net/huli870715/article/details/7887818
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Thank you ! Although there is no cause, but still thank you very much .