Validation on the fly?

Sorry Simon, but I couldn’t help finding the irony of this error on a page titled “Validation on the Fly” rather funny:

XML Parsing Error: not well-formed
Location: http://simon.incutio.com/archive/2002/10/21/validationOnTheFly
Line Number 67, Column 14:
$entry =~ s/&(?!amp;|#|[\w] ;)/&/g;
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