Error message appears saying the username is required to be lowercase

When attempting to create an account, enter a name like JibberJim as your username, the page will come back saying it's not a valid username it must be lowercase.

This is clearly a user interface bug, the user should not be expected to care about minor details such as this, the system should automatically lowercase the username and the user never need know. She should certainly not be expected to re-enter passwords.