LDAP Authentication fails using docker login

After integrating with AD/LDAP and creating a generic role for read access to a hosted docker repository(s). The role is assigned to an active AD User. Docker logins for this user fail with the following.

```
Error response from daemon: no successful auth challenge for https://registry.dev.example.local/v2/ - errors: [basic auth attempt to https://registry.dev.example.local/v2/ realm "Sonatype Nexus" failed with status: 401 Unauthorized]
```

The same user can login to the Nexus UI fine.

Creating a local test user account and assigning the role works fine for docker login.
Tested with Docker v1.10 and v1.7