Perl: HTML::PrettyPrinter - Handling self-closing tags

Question

I am a newcomer to Perl (Strawberry Perl v5.12.3 on Windows 7), trying to write a script to aid me with a repetitive HTML formatting task. The files need to be hand-edited in future and I want them to be human-friendly, so after processing using the HTML package (HTML::TreeBuilder etc.), I am writing the result to a file using HTML::PrettyPrinter. All of this works well and the output from PrettyPrinter is very nice and human-readable. However, PrettyPrinter is not handling self-closing tags well; basically, it seems to be treat the slash as an HTML attribute. With input like:

<img />

PrettyPrinter returns:

<img /="/" >

Is there anything I can do to avoid this other than preprocessing with a regex to remove the backslash?

Not sure it will be helpful, but here is my setup for the pretty printing:

my $hpp = HTML::PrettyPrinter->new('linelength' => 120, 'quote_attr' => 1);
$hpp->allow_forced_nl(1);

my $output = new FileHandle ">output.html";
if (defined $output) {
    $hpp->select($output);
    my $linearray_ref = $hpp->format($internal);
    undef $output;
    $hpp->select(undef),
}