I have to agree with Phil (we usually do) - your call to
http://servername/lawson/portal calls the index.htm file which just displays that login screen. If you get into the login behind it and redirect the call to ~/servlet/Profile and the other servlets that get loaded you might bypass the login screen.
If you did some javascript testing on the frontnd you might be able to bypass it if the appropriate variables are already set, but be careful - doing that might also open you up to a security issue by anyone who knows how to reset their own variables.