JSPs writing binary data

Hi,
I'm trying to develop a JSP that returns binary data in the form of a jpeg image.
I found this on google where one of the replies correctly states that to be compliant I need to use XML JSPs:
http://www.caucho.com/quercus/faq/question.xtp?question_id=1005
This is what I am now doing but I am getting exceptions about:
"java.lang.IllegalStateException: getOutputStream() has already been called for this response"
I have traced this to be on the very last line of the blah_jsp.java file created by tomcat:
"if (_jspxFactory != null) _jspxFactory.releasePageContext(pageContext);".
My code looks like this:
<jsp:root xmlns:jsp="http://java.sun.com/JSP/Page" version="1.2">
<jsp:directive.page contentType="image/jpeg" />
<jsp:declaration><![CDATA[ .... ]]></jsp:declaration>
<jsp:scriptlet><![CDATA[
try {
updateImage();
response.getOutputStream().write( apodImageData );
} catch (Exception e) {
out.println( e.toString() );
StringWriter sr = new StringWriter();
e.printStackTrace( new PrintWriter( sr ) );
out.println( sr.toString() );
]]></jsp:scriptlet>
</jsp:root>
Any ideas? Is there a way to stop the container produced java file from tampering with out? Obviously my code is working but the final line of the container produced code is failing because I've manually been using result.getOutputStream().
Any ideas?

Have just found this after many hours of searching:
http://www.mooreds.com/weblog/archives/000018.html
The upshot is that TC4 is non compliant in this area, TC5 is fixed..

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