[2005] XML > AppendChild

I have a single XML file that will most likely remain small for the most part.

Heres the structure:

<?xml version="1.0" encoding="utf-8"?>
<Defigo>
<Server host="domain.com" type="Web" />
<Server host="127.0.0.1" type="Database" />
</Defigo>

I have a form that has 2 textboxes. serverHost and serverType. I'm trying to add a new entry like this:
<Server host="domain.com" type="Web" />

when I click buttonCreate.

I'm able to read the nodes just fine, but writing is a whole new story.

I am trying to understand the function of the XMLDOM command appendChild.

Here is some code that loads in a simple XML file, that creates a copy of the XML object loaded in, and adds a new 'name' node and then a subsequnt text node of value 'John'.
This is all well and good, but it also appears that the orginial XML object is also modified.
It appears that the offending line is this line;
objCurrNode.appendChild(objNewNode)

What confuses me, is I have created a copy of the original object, performed some functions on various instances of the copy, appended the result back to the copy, the copy changes (as you would expect) but so too does the orignial object (which I didn't expect)

here is the full vbs

Code:

---

Dim objXMLDoc
Dim objCurrNode
Dim objNewNode
Dim objNewText

Set objXMLDoc = CreateObject("Microsoft.XMLDOM")
objXMLDoc.async = False
objXMLDoc.load("names.xml")

MsgBox "value of objXMLDoc in memory=" & vbCrLf & objXMLDoc.xml

Set objNewNode = objXMLDoc.createElement("name") ' within the XML document object (objXMLDoc), create a new element called objNewNode and assign it the value 'name'

Set objNewText = objXMLDoc.createTextNode("John") ' within XML document object (objXMLDoc), create a text node called objNewText and assign it the value 'John'
objNewNode.appendChild(objNewText) ' within the node 'objNewNode' (that is called 'name'), append to it a child by passing it the node 'objNewText' (that has a value of 'John')

Set objCurrNode = objXMLDoc.documentElement ' assign to the variable objCurNode, the whole of the XML document object called objXMLDoc

MsgBox "value of objCurrNode in memory1=" & vbCrLf & objCurrNode.xml

objCurrNode.appendChild(objNewNode)
MsgBox "value of objCurrNode in memory=" & vbCrLf & objCurrNode.xml
MsgBox "value of objXMLDoc in memory2=" & vbCrLf & objXMLDoc.xml

---

and here is the copy of the original xml file called names.xml;

Code:

---

<names>
  <name>Alice</name>
  <name>Bert</name>
  <name>Charlie</name>
  <name>Diane</name>
  <name>Eric</name>
</names>

---

Please could someone explain why it appears that appendChild is changing the original XML object variable (objXMLDoc)?