Word doc to pdf conversion?

I am trying to find a way to convert a Word doc saved in the XML format to a PDF file (that looks like the original Word doc). Yes, there are all kinds of ways to do this interactively. What I need is something that can be run as a background process so that when XML files are placed in a certain directory a cron job can periodically convert them to a PDF file. I would assume there are some Windows libraries that have something like this, but I am trying to do this on UNIX. Without 1,000 hours of programming.