So I stuck with document.all and removed 'elements' from my function:
Code:
function obtainTotals(data) { //this is used for processing/updating order totals
// Set up data variable
var formdata = "";
// Loop through form fields
for (i=0; i < data.length; i++)
{
formdata = formdata + data[i].name + "=" + escape(data[i].value) + "&";
}
makePOSTRequest('filename', formdata, 'totals');
}//end function obtainTotals(obj) {
And.... it works the same way. The AJAX generated data doesn't show up in the $_POST array (or $_GET or $_SESSION for that matter).