Saxon

QT4 test unparsed-text-available-012a attempts to get the same URI twice (once with a specified encoding, once without).

The first attempt fails, and attempts to record the fact that it has failed in a cache, so that subsequent attempts will also fail (the results are required to be stable). However, the second attempt is reported as success, on the basis that a value is found in the cache - it isn't being recognized as a value signalling that the previous attempt failed.