Use a data format that can be extended, like YAML.
Wow I never knew about that one - thats probably the solution. As I see it, the advantage of an XML solution is that the structure is well understood which means its easier for the logfile to be self documenting and thus is more maintainable in the event of my falling under a bus.
If you insist on using XML, then parse it by pushing a fake root around of the file...
That was something I wanted to avoid. Its OK for a small logfile that can be hndled with XML::Simple, but if(when?) the log file grows then I'd like to migrate to XML::Twig or similar and then I can't do that.