CiviGroup Roles Sync Slows User Login

I am current running a number of different installs of CiviCRM 4.4.5, 4.4.4 & 4.4.3 all tied to Drupal 7. There is one particular install which has just over 60 roles in drupal and 60+ groups in Civicrm that CiviGroup Roles Sync must synchronize to manage permissions. I notice that login takes a very long time whenever the CiviGroup Roles Sync module is enabled to facilitate this synchronisation. We have seen login times of between 30 and 60 seconds. If I disable the module login happens at its usual speed. Please verify and advise as to a solutions to this issue.