Yup, just change it to &. XML supports - I think - five named entities: ", ', <, > and &. Note that you should also do this for all non-standard characters (i.e. above 127 in the ASCII char set).

s/([^\x1f-\x80])/"&#".ord($1).";"/ge;
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Our Fearless Leader (tm) had the same problem with the xml nodes, and this is how he fixed, IIRC.

[ ar0n ]