function arras_get_thumbnail($w = 630, $h = 250) {
	global $post;
		
if ( function_exists('has_post_thumbnail') && has_post_thumbnail($post->ID) ) {
 $thumbnail = wp_get_attachment_image_src( get_post_thumbnail_id($post->ID), full );

		if (!$thumbnail[0]) return false;
	else return get_bloginfo('template_directory') . '/library/timthumb.php?src=' . $thumbnail[0] . '&w=' . $w . '&h=' . $h . '&zc=1';
 
 } else {
 $thumbnail = get_post_meta($post->ID, ARRAS_POST_THUMBNAIL, true);
 }
	
	if 	(!$thumbnail) {
	return false;
	} else {
		if (ARRAS_THUMB == 'phpthumb') {
			return get_bloginfo('template_directory') . '/library/phpthumb/phpThumb.php?src=' . $thumbnail . '&w=' . $w . '&h=' . $h . '&zc=1';
		} else {
			return get_bloginfo('template_directory') . '/library/timthumb.php?src=' . $thumbnail . '&w=' . $w . '&h=' . $h . '&zc=1';
		}
	}
}