dashboard-logo.php

<?php

// In den Administrativen Header einhaken - Eigenes Logo für den Dashboard-Bereich von WP
add_action('admin_head', 'ah_custom_logo');

function ah_custom_logo() {
echo '
<style type="text/css">
#header-logo { background-image: url('.get_bloginfo('template_directory').'/images/custom-logo.png) !important; }
</style>
';
}