Current version implements full StAX 1.0 API, to the best understanding
of the author. Note, however, that 1.0 version of the specification
has quite a bit of ambiguity regarding several features (see below for
examples).

First, there are some features where implementation could
arguably be improved, to bring it to closer to the spirit of
the specification:

* SAX input (source) and output (result) objects can not be used with
  XMLInputFactory and XMLOutputFactory.
* DOM (output) result objects can not be used XMLOutputFactory.

Also, following 3.0 features may be considered non-compliant (either
regarding Stax 1.0, or XML 1.0), based on discussions on stax-builders
list:

* Reporting of SPACE outside of the root element seems like the wrong
  thing (based on xml specs, Infoset, and to lesser degree even Stax
  javadocs), even though the reference implementation also reports these.
  Since this is a configurable property, it is easy to just change the
  default to 'false' (do not report), from its 3.0 setting 'true'.
  Eventually the feature can also be obsoleted.
* Returning null for "no namespace", while unspecified (or inconsistently
  defined) in Stax 1.0, seems incompatible with JDK 1.5 definition of
  XML handling. 1.5 seems to default to "" everywhere, so perhaps it is
  best to follow that practice, even though philosophically null seems
  like a more fitting choice. StaxTest and the ref. impl. should be similarly
  changed, if this is done: also, this should not be done before 4.0.

Some of open questions regarding exact meaning of the specification
include:

* If entities are NOT to be expanded, how does this affect:
   * Pre-defined entities (amp, lt, gr, apos)? Currently Woodstox leaves
     this unexpanded as well, and returns them as separate entities;
     this seems close to what XML specs indicates (these entities are
     no different from explicitly declared ones), but is not necessarily
     intuitive from application's point of view.
   * Entities in attribute values. Since there is no mechanism to return
     such events, Woodstox expands such entities automatically. The
     alternative would be to signal an error.