User not redirected back to referrer when joining a group

When a user clicks the link within a group invitation e-mail and is not logged in they are redirected to the /user page. A message is displayed at saying:

"In order to join this group, you must login or register a new account. After you have successfully done so, you will need to request membership again."

login and register are both links which contain a destination param to take the user back to automatically accept the join invitation however if the user uses the login boxes on the /user page they are not redirected as the destination param is missing.

changing line 282:
drupal_goto('user');
to:
drupal_goto('user', $dest);

(sorry I haven't provided a patch, pushed for time, I will come back and try to sort it out)