my @list = $tree->findnodes('//select[@id="categoryID"]') || warn "couldnt find any nodes for select & name of categoryID";

while (my $row=$cat_sth->fetchrow_hashref ) {
my $node = XML::LibXML::Element->new('option');
$node->setAttribute('value',$row->{id});
if ($row->{id} == $params->{categoryID}) {
            $node->setAttribute('selected','selected');
        }
my $text = XML::LibXML::Text->new($row->{description});
$node->appendChild($text);

$list[0]->push($node);