Group associations are not preserved for synced users with mixed-case usernames

The setup is as follows:

LDAP > JIRA > FishEye/Crucible

With the following option enabled, users with mixed-case usernames in LDAP are synced but are not associated with their groups in FishEye/Crucilble. The users are listed in the Users list (in lowercase):

FECRU Administration >> Security Settings >> Authentication >> Usernames >> Force Lowercase Username = ON