如何拼接两结构相同的XML文档

在工作中遇到这样的问题：
在主表单中用户可以添加5项产品
多余的产品必须打开另外一张表单以附件形式添加
最后保存的时候将主表单和附件表单的数据一起提交，以下是我的实现方式：
var [b]xmlAccessories = createDomDocument();
var [b]xmlInsertDoc = createDomDocument();[/b]

xmlAccessories.loadXML(“<DETAILS>
<TABLE>
<Res>6</Res>
<Type>6</Type>
<Magnitude>6</Magnitude>
<Budget>6</Budget>
<Price>36</Price>
<Date>2009-09-06</Date>
</TABLE>
<TABLE>
<Res>7</Res>
<Type>7</Type>
<Magnitude>7</Magnitude>
<Budget>7</Budget>
<Price>49</Price>
<Date>2009-09-07</Date>
</TABLE>
</DETAILS>”);
xmlInsertDoc.loadXML( "<DETAILS>
<TABLE>
<Res>1</Res>
<Type>1</Type>
<Magnitude>1</Magnitude>
<Budget>1</Budget>
<Price>1</Price>
<Date>2009-09-01</Date>
</TABLE>
<TABLE>
<Res>2</Res>
<Type>2</Type>
<Magnitude>2</Magnitude>
<Budget>2</Budget>
<Price>4</Price>
<Date>2009-09-02</Date>
</TABLE>
<TABLE>
<Res>3</Res>
<Type>3</Type>
<Magnitude>3</Magnitude>
<Budget>3</Budget>
<Price>9</Price>
<Date>2009-09-03</Date>
</TABLE>
<TABLE>
<Res>4</Res>
<Type>4</Type>
<Magnitude>4</Magnitude>
<Budget>4</Budget>
<Price>16</Price>
<Date>2009-09-04</Date>
</TABLE>
<TABLE>
<Res>5</Res>
<Type>5</Type>
<Magnitude>5</Magnitude>
<Budget>5</Budget>
<Price>25</Price>
<Date>2009-09-05</Date>
</TABLE>
</DETAILS>");
var nodeAccess = xmlAccessories.documentElement;
var nodeDetails = xmlInsertDoc.documentElement.selectSingleNode("DETAILS");
//var nodeTable = nodeAccess.firstChild;
//while(nodeTable!=null)
//{
// nodeDetails.appendChild(nodeTable.cloneNode(true));
// nodeTable=nodeTable.nextSibling;
//}

for(var i=nodeAccess.childNodes.length-1;i>=0;i--)
{
var nodeTable = nodeAccess.childNodes[i];
nodeDetails.appendChild(nodeTable);
}[/b]