I'm having problems getting my program to work correctly. It keeps telling me Undefined subroutine &SUPER::start_document called at safari.pl line 26. Since my script is less than finished, I have an example script taken from "XML and Perl" that does the same thing when I run it.

use XML::Parser::PerlSAX;
use XML::Handler::Subs

#
# initialize the parser
#
use XML::Parser::PerlSAX;
my $parser = XML::Parser::PerlSAX->new( Handler => H1_grabber->new(  )
+ );
$parser->parse( Source => {SystemId => shift @ARGV} );

## Handler object: H1_grabber
##
package H1_grabber;
use base( 'XML::Handler::Subs' );

sub new {
    my $type = shift;
    my $self = {@_};
    return bless( $self, $type );
}

#
# handle start of document
#
sub start_document {
  SUPER::start_document(  );
  print "Summary of file:\n";
}

<snip>
[download]

The part I've snipped out just contains handlers for the various HTML elements in the file (s_h1 for an h1 start tag, e_h1 for an h1 end tag, etc.) and shouldn't affect the above section of script in any way. Does anyone know why this script doesn't work?