Users sync

Hi guys
Firstly, i want to say thanks to VB for created such a great contrib like phpbb integration module. But i had one reservation - user sync not work correctly. When i changed username in Drupal in phpbb3 was created new user and when i changed username in phpbb3 in drupal username is still same. Can anybody say me how i can easly fix that? I use 6.x-2.0-beta7 and phpbb3.
Cheers