Fix the Internet connection problems for the systems behind proxies / firewalls which requires authentication.

It's a big pain to mess with the config files to set up all shipped programs to work ok in such an environment. The System | Preferences | Network Proxy... Manual Proxy Configuration, [Details] button (...enter here your username, pwd) has a very 'fuzzy' effect (even if we press [Apply System Wide...] button) - some programs work, some don't (including apt-get) etc.

For more details you can have a look at http://askubuntu.com/questions/6340/cannot-connect-to-intern...

Can we have a centralized, streamlined, intuitive approach for this which really works?