This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
Just put the full absolute path of the properties file. Don't use a relative path unless you are sure you can control the current working directory when the application is run, and if you can then make the path relative to that directory.