By using XSLT transformation technique how do I map an XML file to another XML file?
This tool claims to do it:
You can also try some other tools mentioned here: http://www.sys-con.com/xml/wbg/open.cfm?BType=XSLT+Utilities
Unfortunately to create XSL this way you would have to have examples of XML files that fully exercise all allowed elements of your DTD. To come up with complete XML that utilizes all the elements described in DTD maybe fairly difficult.