Open the PDF in Designer and under the File/Form Properties/Preview menu you can "Generate Preview Data". Now that you have a data structure you can open it with your favorite XML editor (I use XMLSpy). There is an option to create a schema from the data file in that product. I do believe that there are a number of free websites that do ths as well. I did a google search on "Convert XML file to schema" and got numerous hits.
Paul
