The problem is that you don't have a well-formed XML file. If it were well-formed,
there would be a root element, which is the ancestral of every other ones. Something like this:
<root>
<CVS>
$Id: File_Find.pl,v 1.1 2006-12-17 19:25:03 eric Exp $
</CVS>
<DATE>2006-12-10</DATE>
...
<ARTICLE>
foo bar baz
</ARTICLE>
</root>
I think if you do this simple correction, XML::Simple will work right for you. And, by the default,
this root element disappears, so that you'll get at the first level a hash with the keys you want:
CVS, ARTICLE, DATE, etc.
You could always try your XML files against a typical browser (like FireFox, Opera, IE, etc.)
to see if they are well-formed or if some error is pointed.