With XML and HTML, a more challenging game is possible ... “character entities” such as “#x0041”, which is the Unicode code for a capital A character. The multiple uses of ampersand ...

Unlike HTML, XML can link an unlimited combination of ... But the XML framework introduces a more complex character set routine, Unicode, to facilitate more complex data typing.

The requests all follow a general format, so I came up with an XML DTD to describe them ... So I picked two Unicode chars that are outside the normal range of chars I'd send.< ...