Visitor user registration fails when e-mail verification not required

1) Log in, then go to:
Administer -> Configuration and modules -> People and permissions -> Account settings

2) Under "Registration and cancellation" set "Who can register accounts?" to "Visitors", and then uncheck "Require e-mail verification when a visitor creates an account."

3) Submit the Account settings form.

4) Log out, then go to http://example.com/user/registration and attempt to register as a user. And you will get the following error:

Warning: Missing argument 2 for user_authenticate(), called in (directory of the site)/modules/user/user.module on line 2982 and defined in user_authenticate() (line 1718 of /Users/lonelyrobot/Sites/head/modules/user/user.module).

and the account has not been created.