my $tmpl = HTML::Template->new(filename => "/srv/www/site/news.html");

print $tmpl->param(\%params);
print $tmpl->output();

my $htc = HTML::Template::Compiled->new(...);
$htc->param(
    header => $header_aus_db,
    footer => $footer_aus_db,
);
# template
<%include_string header %>
...
<%include_string footer %>

my $str = "Hier die News: <TMPL_INCLUDE NAME=news.html>";

&template($dbh,  \%params, $str);

sub template {
	my ($dbh, $paramsref, $data) = @_;

	my $tmpl = HTML::Template->new(filename => "/srv/www/projektgemeinschaft/main.html");

	my %params = ();

	$params{$_} = $paramsref->{$_} for keys %{$paramsref};

	my $textile = new Text::Textile;
	$data = $textile->process($data);

	$params{'CONTENT'} = $data;

	$tmpl->param(\%params);
	print $tmpl->output();
}