Assigning an extension to the user

Is there any way to assign an asterisk extension to the user, during registration?
- Website will communicate with asterisk server and creates an extension with predefined extension settings.
- Drupal UID can be used as "accountcode" field in extension settings
I think this feature can help enough to integrate drupal with asterisk. Rest of integration can be done with other drupal modules such as views, asteriskcdr.