I'm not an AJAX developer but I think that you should select a more powerful Ajax and Javascript framework, instead of coding all the xml and javascript stuff by yourself.
I used JQuery for other purposes and I think it's a very powerful framework, full of plugins and community rich. These are some starting points: - http://docs.jquery.com/Ajax - http://www.ibm.com/developerworks/library/x-ajaxjquery.html Good AJAX programming! ROb
