get wordpress image attachment and use tim thumb to crop

<?
 
// usage <?php postimage(180,135);?>
// or whatever dimensions you want
// requirements: have tim thumb in your theme directory
 
function postimage($width,$height) {
    $scriptpath = get_bloginfo('template_directory'); 
    $attachments = get_children(array('post_parent' => get_the_ID(), 'post_type' => 'attachment', 'post_mime_type' => 'image', 'orderby' => 'menu_order'));
    if (!is_array($attachments)) {
    $image = $scriptpath."/images/default.gif";
        echo '<img src="'.$scriptpath.'/scripts/timthumb.php?src='.$image.'&w='.$width.'&h='.$height.'&zc=1" alt="" />';
    }
    else {
    $img = array_shift($attachments);
    $imagelink = wp_get_attachment_image_src($img->ID,'full');
    $image = $imagelink[0];
        echo '<img src="'.$scriptpath.'/scripts/timthumb.php?src='.$image.'&w='.$width.'&h='.$height.'&zc=1" alt="" />';
}
}
 
?>