Vista - passing multiple XML nodes to a binding converter

Hi,

I'm looking to implement something similar to an example by Bea Costa
( http://www.beacosta.com/blog/?p=35 ), but using an XML data source
instead of a C# data model.

Image my XML data source looking like this:

<?xml version="1.0" encoding="UTF-8"?>
<points>
<point x="275" y="100" >A</point>
<point x="375" y="200" >B</point>
<point x="275" y="300" >C</point>
<point x="175" y="200" >D</point>
</points>


In Bea's example, she binds to the C# data model like so:

<Polygon Fill="#CD5C5C" Points="{Binding Source={StaticResource src},
Path=Points, Converter={StaticResource converter}}"/>


I assumed I would be easily able to switch it to XML by defining my
XmlDataProvider (with key="pts") and bind to it as such:

<Polygon Fill="#CD5C5C" Points="{Binding Source={StaticResource pts},
XPath=points, Converter={StaticResource converter}}"/>


However, this doesn't work. The value object passed to the converter
appears as the string "ABCD". How can I get it to pass the converter a
collection of point nodes instead of a concatenated list of the nodes
content? I've been told to add "path=InnerXml" to the binding and then
parse the resulting XML, but this strikes me as quite inelegant.

Any ideas?

Cheers,
-robin