Cant register new users on gitorious

I'm using the AMI and when I try to register a new user using the /users/new path I get an error 500.

If I manually create a user in the administration it works fine. I've been able to login with the administrator account and create my own new account. But I want to allow people who have the server URL to register on their own.

Am I missing some kind of configuration issue?

Thanks!