I've been using spider.pl from swish-e-2.1-dev-25-2002-02-12 and noticed
that the subroutine I defined under filter_content was never getting called.
Taking a look at the spider code I found the following:

    } else {
        return $links_extracted unless check_user_function( 'content', $uri,
$server, $response, \$content );

I changed this to:

    } else {
        return $links_extracted unless check_user_function(
'filter_content', $uri, $server, $response, \$content );

and now the subroutine is called.  Incidentally, I found the same problem in
swish-e-2.1-dev-25-2002-02-26.  Thanks.

Adam Edelman