Got it guys ... There is a substantial amount of issues for the AngularJS/PhoneGap/WindowsPhone combination. This one was solved by https://github.com/angular/angular.js/issues/2303?source=cc#issuecomment-20770025.
Essentially, because windows phone uses a weird protocol prefix with a single forward slash (x-wmapp0:/)
, the $location initializer goes nuts and that triggers an error which seamingly exposes itself in this weird error message, completely unrelated to the error :-(
I'm about to propose a pull-request on this fix to the AngularJS repo on GitHub.