I too get the error, but not every time that I run it. If I catch the culprit, I will let you know.
I am using 9.00.4262.00 (X64).
The error is;
Msg 6841, Level 16, State 1, Line 24
FOR XML could not serialize the data for node 'processing-instruction(definition)' because it contains a character (0x0000) which is not allowed in XML. To retrieve this data using FOR XML, convert it to binary, varbinary or image data type and use the BINARY BASE64 directive.
Great article and very useful.