Are you sure hand customizing a derivative of Config::Tiny wouldn't get you where you need to go, rather than the large overhead of loading RecDescent? Config::Tiny is a minimalistic way of loading a .ini style config file, and it spits out a simple hash structure. It looks VERY close to what you are doing...

I reckon you could do it with half a dozen lines of code...

Of course, I could have a complete wrong grasp of the task...