Java EE (Java Enterprise Edition) General Discussion

I'm experiencing some very interesting behavior.

I'm using form-based authentication to secure all (/*) pages of my Tomcat 4.0.3 web-app. When an un-authenticated user tries to access a secured resource, they are rightly forwarded to the correct login.jsp page as detailed in the <login-conf> element of my web.xml file.

The login page has the appropriate <form action="j_security_check" method="post"> form
and two text fields named "j_username" and "j_password".

The problem is that when a tomcat-user with the appropriate role logs in, MS FrontPage launches instead of the request being forwarded to the requested resource!!!

Can anyone explain this behavior?