Xml Comparison in C#

Hi

I'm trying to compare two Xml files using C# code. I want to ignore Xml syntax differences (i.e. prefix names). 

Question 1: What is the best way to do it?

Meanwhile I'm using Microsoft's XML Diff and Patch C# API. It works for some Xml's but I couldn't find a way to configure it to work with the following two Xml's:

XML A:

<root xmlns:ns="http://myNs">

<ns:child>1</ns:child>

</root>

XML B:

<root>

<child xmlns="http://myNs">1</child>

</root>

Quesiotn 2: Am I right that these two xml's are semantically equal (or isomorphic)?

Question 3: Can Microsoft's XML Diff and Patch API be configured to support it?