That seems to be it - there is an unresolved bug report posted here:
https://rt.cpan.org/Public/Bug/Display.html?id=50171
Fri Oct 02 14:07:24 2009
'<readonly/>' is translated in the generated hash to readonl. the 'y' is cut.

In reply to Re^3: XML to Hash Truncating Keys Problem by tangent
in thread XML to Hash Truncating Keys Problem by Wayne

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