Updating Eclipse from behind a proxy was quite counter-intuitive for me; or was it??? I had expected to find the proxy setting in the same window where the updater hooks up to the internet. Unfortunately, with Eclipse, it was under Window > Preferences > Install/Update > Use HTTP Proxy… But this option of not having to hunt around the eclipse site for the plug-ins is a real killer concept. Saves a lot of time too. One up to the Eclipseproject.