content or excerpt

This is the conditional code i used with WP 1.2. Now is no more working on WP 1.5. What i have to change? It is for putting the excerpt instead of the content only if I have it.
<?php
if(!$post->post_excerpt) {
the_content(‘<img src=”kling.gif” /> more…’);
} else {
the_excerpt();
?>
” rel=”bookmark” title=”Permanent Link to <?php the_title(); ?>”><img src=”kling.gif” /> more…
<?php
}
?>