mirror.setId("local");
        settings.addMirror(mirror);
        mirror = new Mirror();
        mirror.setId("illegal\\:/chars");
        mirror.setUrl("http://void");
        mirror.setMirrorOf("void");
        settings.addMirror(mirror);

        SimpleProblemCollector problems = new SimpleProblemCollector();
        validator.validate(settings, problems);
        assertEquals(4, problems.messages.size());