After installing Eclipse Kepler, all required JRE, and the Force.Com IDE. I then create a new Force.Com project and provide valid login information to my org I get the following error after a few seconds:
Unable to load org details
Looking at the Salesforce log, I don't see any logins. I am behind a corporate firewall, which Eclipse has correctly identified. My General -> Network Connections are using the "Native" setting that Eclipse found (the IP and Port is valid).