Bug 531107: [Windows] Starting an extension resulted in "deep recursion on subroutine" because File::Spec::Win32 was doing a "require" in case_tolerant, which recursed into Bugzilla::Extension::my_inc in an infinite loop.
Patch by Max Kanat-Alexander <mkanat@bugzilla.org> (module owner) r=mockodin, a=mkanat