XML을 OBJECT로 만들어내는 코드가 IE에서 점차 느려집니다. 어떻게 해야 할까요?

<MEMBERS>
  <MEMBER>
    <NAME>Han-gil Lee</NAME>
    <TEL>000-000-0000</TEL>
  </MEMBER>
  <MEMBER>
    <NAME>Han-gil Park</NAME>
    <TEL>111-111-1111</TEL>
  </MEMBER>
</MEMBERS>

{"MEMBERS":
  {"MEMBER":{"NAME":"Han-gil Lee","NAME_list":["Han-gil Lee"],"TEL":"000-000-0000","TEL_list":["000-000-0000"]},
  "MEMBER_list":[
     {"NAME":"Han-gil Lee","NAME_list":["Han-gil Lee"],"TEL":"000-000-0000","TEL_list":["000-000-0000"]},
     {"NAME":"Han-gil Park","NAME_list":["Han-gil Park"],"TEL":"111-111-1111","TEL_list":["111-111-1111"]}]},
  "MEMBERS_list":[
     {"MEMBER":{"NAME":"Han-gil Lee","NAME_list":["Han-gil Lee"],"TEL":"000-000-0000","TEL_list":["000-000-0000"]},
     "MEMBER_list":[
        {"NAME":"Han-gil Lee","NAME_list":["Han-gil Lee"],"TEL":"000-000-0000","TEL_list":["000-000-0000"]},
        {"NAME":"Han-gil Park","NAME_list":["Han-gil Park"],"TEL":"111-111-1111","TEL_list":["111-111-1111"]}
     ]}
  ]
}

XMLDomParser.prototype = {
 
	parse : function(xmlDomData) {
 
		return this.scanner(xmlDomData.childNodes)
	},
 
	scanner : function(childs) {
		var pool = new Object
		var count = 0
 
		for(var i=0; i<childs.length; i++) {
 
			var nodeName, nodeValue
 
			nodeName = childs[i].nodeName
			if(nodeName=="#text") continue
 
			nodeValue = this.scanner(childs[i].childNodes)
 
			//이 요소가 처음 발견되었는가?
			//이 부분이 속도가 늦어지게 하는 주범같음
			//객체에 프로퍼티를 만드는것,배열에 값을 넣는 것
			if(typeof(pool[nodeName])=='undefined') {
				pool[nodeName] = nodeValue
				pool[nodeName + "_list"] = new Array
			}
			pool[nodeName + "_list"].push(nodeValue)
 
			count++
		}
 
		//하위 요소가 없었다면 값을 리턴
		if(count==0) return this.getElementText(childs)
		else return pool
	},
 
	getElementText : function(elem) {
		try {
			return elem[0].nodeValue
		} catch(e) {
			return ""
		}
	}
}