When running Preflight in XML mode, the latest Preflight version (I used the JAR from build #747) sometimes produces output that contains characters that are illegal in XML. This can cause unexpected behavior if such files are further processed with tools that expect well-formed XML. See attached PDFs, which all result in illegal characters in the description of a 1.0 Syntax error, Error: Expected a long type. Output of older versions of Preflight didn't contain these illegal characters; instead they would give something like actual='/O', actual='Pages'. etc. So I suppose this must have been caused by a fairly recent change.
See attachments below.