Message to read replies

Hi,

I have set all categories that replies can not be read by Guests. A guest can now see how many replies there are but not what the replies are. So far so good. But the message only says that the guest doesn't have rights to read the replies. Is there a setting that the message can show that you need to register to read the replies, including a registration link? A guest is then more inclined to register with the site.

Regards,
Ewoud