I stole this from a mail Kip Hampton sent me a few weeks ago with immensely useful documentation that somehow never got published. It's a chart that lists all the PerlSAX events one could handle, classified by handler type and by SAX version.
It may change a bit in the future in that xml_decl may be moved to SAX2 (it probably shouldn't be available but people want it).
You can get it from http://berjon.com/perl/xml/sax-chart.html. Comments are, of course, welcome.