CDATA! I think XML::Parser recognizes it. Something like this, I believe:

<txt><![CDATA[
    anything in here should be ok like <tags> & entities
    and will be taken literally
]]></txt>
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Is that the right tag? Anyway, that essentially tells the parser not to parse anything inside that. I'm pretty sure it works with XML::Parser but you'll have to test it to be sure.

local $_ = "0A72656B636148206C72655020726568746F6E41207473754A";
while(s/..$//) { print chr(hex($&)) }
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