To contribute to the symfony project, you need an account. As of now, this account will allow you to interact with:

Please provide a valid email address as it will be used to notify events about your plugins (new releases, requests to become a contributor, ...) and your trac tickets (new comment on your tickets, resolved tickets, ...).

After signing up, we highly recommend you to also create an account on SensioLabs Connect, which is the new account management system for Symfony2. Read more in the announcement blog post.