Project: rtf2xml: convert MS RTF to XML and not the inverse!
Also there is source code available for rtf to xml here is the link
http://sourceforge.net/projects/rtf2xml/
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Consists of three stand-alone applications: fo2rtf/fo2wml (command-line executables) and XSL Utility (graphical user interface) and it's no good!
Now coming to your query. If you are looking for something in PH as you have posted in PHP forums then I dont think the link will help but you can have a look at it.
http://www.xmlmind.com/foconverter/xml_to_rtf.html
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