The plugin still works, you just need to make a small modification.
Open the file simple-tags.php, on line 35 you should see this:
if ( strpos($wp_version, ‘2.7’) !== false || strpos($wp_version, ‘2.8’) !== false ) {
change it to this:
if ( strpos($wp_version, ‘2.7’) !== false || strpos($wp_version, ‘2.8’) !== false || strpos($wp_version, ‘2.9’) !== false ) {
Like magic it works.