How could I load the content of a page into one iFrame depending on
what hyperlink I clicked on another iFrame?

I would like to use the example shown in the article "Build an
XML-based Tree Control with JavaScript"
(http://www.devx.com/getHelpOn/Article/11874) written by Tom Duffy.

Using the article as a reference, the last listing shows how both
iFrames are defined; one is for the tree and the other one for the
content of a specific branch.
My understanding is to modify the JavaScript file xmlTree.js so that
it includes a function that responds when a leaf is clicked and
dinamically loads the content into the iFrame.
I suspect changes to the XSLT file are needed also but I'm not sure
where to apply them.

Ideally I could attach an anchor tag to the leaf, including a url with
querystring values and that successfully loads files locally
or from a server.

It is important that the solution works at least for IE 5+ and Firefox 1.0+

Thanks in Advance.