I thought I did this one time before... but upon further review. What I did was put an call to a function when the field was clicked;

<td><span onclick="fnShowResults()" Datafld="AccountNum"></span></td>

Then in the fnShowResults function I parsed the value of the field,
function fnShowResults(){
lcValue = window.event.srcElement.parentElement.parentElement.cells(1).innerText;
lcValue = "my_asp.asp?remote="+lcValue;
parent.frames(1).location = lcValue
}

You get the same kind of results, but it's a little more generic and you don't have to mess with your XML data.

HTH