We've been using a package called JFig to manage system configuration and properties. JFig uses OO concepts such as inheritance and variable interpolation. The result is an extremely flexible dynamic way to manage properties and configurations that solves many of the problems in managing configurations in business environments. Version 1.1 will add an option to set configuration values as properties if necessary as well as adapters to use JFig with Ant and Maven.
I've used JFig on a variety of projects and four development teams are currently using it where I work.