The AElfred parser uses the wrong base URI when
resolving a relative URI in an external entity
declaration. Specifically, it uses the base URI of the
resource containing the entity reference, not that of
the resource containing the entity declaration.
This error is present in the version of the AElfred
parser included in Saxon 6.4.3, and is also present in
all previous versions.
David Brownell says he is working on a fix, and I will
incorporate this in Saxon when it becomes available.