SAX parser for SGML?

Does anyone know of a (preferably open-source) Java-based parser that
produces SAX events from an SGML input document?  

Seems like a tough problem, and I know there are lots of other ways
(likely through ESIS/Pyx kind of stuff) to get there, but it also seems
like something that might well beuseful.

-- 
Simon St.Laurent
Ring around the content, a pocket full of brackets
Errors, errors, all fall down!
http://simonstl.com -- http://monasticxml.org