Problem with member registration and newsletter

I have a problem with the "member registration" module.

I have made a member registration form with the following fields enabled: First name, Last name, E-mail address and Newsletter.

In the front end the user can now register and check the field to subscribe to the newsletter.

The problem is that when I look in the back end, the newsletter box is not checked even though the user selected it when he made the registration.

This is not a problem version 2.6.7 but in 2.7.3 I can't get it to work properly.

Can anyone help me here or please try to see if you have the same problem i version 2.7.3.