posts in restricted categories shown on user profile page

while checking the redirects on my site I noticed that there were a number of 404 hits on certain discussion posts.

These posts belong to a category that is only accessible to a restricted group of users. Further investigation learned that the links that caused the 404s are perfectly fine but only when a user, belonging to the proper group, is logged in. Trying to access that link as 'public' or a different group causes the 404.

The 'referring page' shown in the redirects is the profile page which lists all posts posted by that user.

Now the 'strange' things I see are:

1. The profile page of the user displays posts in restricted categories to users that have no access to those categories. I think those posts should be hidden from users that hav no access to these categories.

2. When a user clicks a link to a post which is restricted to them a 404 is triggered. I think a login page should be shown instead, maybe together with a message that user has no access to that category.

Obviously when these restricted posts are not shown on the user profile, other users cannot click the links and a 404 will never be triggered.....