Interesting question...I would think the extension functionality allows only multiple output *files* only, correct?
It depends. The extensions write to a file or more generally to an URL. However, both Saxon and Xalan have more or less undocumented hooks for getting SAX events or some sort of SAX event extension (for PSVI support). Using it seems somewhat risky though, the APIs have some tendency to change suddenly.
J.Pietschmann
