Looking at the documentation for XML::Simple it looks to me as though this is a feature, not a bug. It seems that XML::Simple strips off the name-value pairs and returns them without the name of the tag. Taken from the EXAMPLES section of the POD for XML::Simple:

When XMLin() reads the following very simple piece of XML:
    <opt username="testuser" password="frodo"></opt>
it returns the following data structure:
    {
      'username' => 'testuser',
      'password' => 'frodo'
    }
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It seems that XML::Simple expects you to use a named variable to hold the contents of the data structure, like this:

use XML::Simple;
my $res = XML::Simple->new()
my $a_tag = $res->XMLin($text);
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