If the entity is not defined by the DTD used on input, teh input is not
well formed and you will get no output at all.
not according to the XML specification
http://www.w3.org/TR/REC-xml#wf-entdeclared
Note that if entities are declared in the external subset or in external
parameter entities, a non-validating processor is not obligated to read and
process their declarations; for such documents, the rule that an entity must be
declared is a well-formedness constraint only if standalone='yes'.
Edward Middleton
XSL-List info and archive: http://www.mulberrytech.com/xsl/xsl-list