On Safari with unescaped ampersands I get the following in the console (printErr is my onerror function):
printData, type=event, status=begin
printData, type=event, status=complete
responseText=<?xml version="1.0" encoding="utf-8"?> <partial-response><changes><update id="ff:diagram"><![CDATA[<div id="ff:diagram"><script type="text/javascript">apprisant.Diagram.update({ d:'ff:diagram', w:770, h:351, mw:'770px', ss:'null', src:'/jsf2demos/agdiagram?id=/orgchart/layout.xhtml:ff:diagram&q=969031&ctr=2&t=dgm&d=s&s=' });</script></div> ]]></update><update id="ff:messages"><![CDATA[<div id="ff:messages"></div>]]></update><update id="javax.faces.ViewState"><![CDATA[-3723890740084867566:4878000296889164334]]></update></changes></partial-response>
printErr, status=malformedXML
desc=NO_MODIFICATION_ALLOWED_ERR: DOM Exception 7
responseCode=200
errorName=undefined
errorMessage=undefined
On IE7 and FF3.5 with escaped ampersands I don't get an error but the diagram goes blank, meaning it couldn't get an image for the url.
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