HI Peter,
I think, it's not possible. I never tried it.
In Standard SAP database only dealt with the PS or PCL file.
and for Inbound documents, only PDF files will be accepted.
WWI reports templates opens in word file format (.doc). and the data can be transferred in .dat file format.
There is no such special function to convert the final report into XML
If I come across any of such things, will get back to you.
find the link below -
http://help.sap.com/saphelp_470/helpdata/EN/9a/a5fdc84e4911d3940a080009b98822/frameset.htm
Regards
kamal