WordPress & Page Redirect

In a previous version of WordPress if a user went to: http://www.myurl.com/mypaper/this-is-it/ it would bring them to a default form for http://www.myurl.com/mypaper/ and pass the (this-is-it) as a hidden form field. So when the user fills this form out and submit it then they gain access to http://www.myurl.com/mypaper/ section were there could be numerous papers. I have now upgraded my version of wordpress and I’m having an issue. Now when I go to http://www.myurl.com/mypaper/this-is-it/ it brings me to a completely different page with no login form. If I go to http://www.myurl.com/mypaper/ then the login form shows. How can I get this working like before? PLEASE HELP…