btm on #chef asked me to file this, still need confirmation, if it's a proper bug. don't have time atm to double check this.
The chef-server-webui service [fail]s after an "apt-get install chef chef-server" from the opscode repository "deb http://apt.opscode.com/ natty-0.10 main" on a fresh and default installation of ubuntu natty server. I changed the chef_server_url asked by debconf to something different than "http://localhost:4000". The /etc/chef/webui.rb doesn't seem to receive this new value, because it still contained "http://localhost:4000" as chef_server_url. All other config files were updated correctly.