saxon: problem reusing XsltTransformer object

Using Saxon-B, I'm trying to follow the javadoc and serially reuse an XsltTransformer object.

I'm thwarted by:

Error 
  XTDE1490: Cannot write more than one result document to the same URI, or write to a URI
  that has been开发者_开发知识库 read: file:/Users/benson/x/btweb/web_2_0/sites/us/errors/404/404.xml.prepared
2011-03-22 11:06:23,830 [main] ERROR btweb.compiler.CompileSite - Site compilation terminated with error.
btweb.compiler.CompilerException: Error running transform Cannot write more than one result document to the same URI, or write to a URI that has been read: file:/Users/benson/x/btweb/web_2_0/sites/us/errors/404/404.xml.prepared

It's probably Saxon-B bug. You can find more information here. According to this site "Fixed in 8.9.0.4".