I’d the same validation problem as waloshin had. The suggested fix didn’t solve my problems with the feed.
After a little tweak made by myself the feed now validates. This will help:
In the last lines of the file includes/theme-head.php there’s a line
$title = $default_title . " » " . get_bloginfo( 'name' );
i’ve changed it to
$title = $default_title . " » " . get_bloginfo( 'name' );
The only thing i’ve changed is the named entity » to it’s numeric entity » and now the feed validates!
