If you can fetch and parse spacfg.xml, then you can fetch and parse other pages as well. http://PHONE_IP/pdir.htm is the page you are searching for (asking for EXPORT). Such page is standart HTML form, so you can use the standard HTTP way to push the edited form back to phone - same way as your's browser do it. Catch the packets *) if you need to see exact content of the data pushed back.
I assume the program recommended to you by works the same way.
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