Ubuntu :: System Settings For Proxy Username And Password?

I'm trying to use Kubuntu 10.04 in a corporate environment. Our environment uses an internet proxy that requires a username and password.Under Ubuntu 10.04, I can use the GUI to set the proxy host, port, username and password. When I do this, all the web browsers work, Snyaptic works, etc.However, under Kubuntu 10.04, the GUI lets me specify a proxy host and port, but doesn't appear to save the username and password. Because of this, I have to manually set the proxy information on my web browser, but the package managers don't work because they can't access the internet. Apparently the ability to specify proxy username and password is either broken or unfinished.