Excel data into Word Userform

I use lists of data made in Excel to populate a Word userform listboxes.
Always have to deal with two files the word template and the excel file. Now
with Word 2007 I see the possibility of having just one file as the docx is
actually a zip file, I want to store the Excel file into this zip, maybe in
an XML format. My question are

How to go from excel data to XML file inside the docx zip ?
how do you link the data in the xml with a form with a Listbox in teh word
doc .
How do you modified the Excel/XML list with out extracting it from the zip
package?
Thanks,
--
Jose Moreno
VB developer