Redirect problem with login

I don’t know if this is a bug, or a problem with my installation. When I navigate to /news/wp-login.php, enter my username and password, it does not let me in the first time. It sends me to /news/wp-login.php?redirect_to=/news/wp-admin/post.php. I then have to enter my username and password again before I am allowed to post. Can someone help?