I found what was causing this, a recent change was made to include the pageMap name into the PageParameters instance of a page, however my Page's didn't have any PageParameters instance, so an NPE was triggered.
I've entered an issue in the source-forge tracker ( 1434999 ) along with a simple patch which is more of a quick fix solution, although I'm now thinking a better quick fix would be to create the PageParameters instance, then follow on to set the pageMap as I'm sure thats now being used elsewhere.
Anyway, at least my app's not crashing, but I'm sure someone with better knowledge of the inner workings of wicket will come up with a more application solution.
Mark
