User isn't automatically logged-in, when "Email Activation" user registration is used

We have "Email Activation" registration mode. This mode allows to validate user's email address and only then make user account active.

This works as follows:

1. user fills-in registration form -> user record is created in "Pending" status and email is sent to user
2. user opens received email and uses activation link in it -> user sees "you've been activated" page on site

I propose we should auto-login user, after 2nd step.

I think, that we should auto-login user, because we do so, when user registration mode is set to "Active".