I can reproduce it on my machine, but this seems to be a bug in ubuntu- system-service, which is the responsible for writing the proxy settings in /etc/apt/apt.conf. g-c-c only calls it via DBus, so it's clearly a bug there?
** Package changed: gnome-control-center (Ubuntu) => ubuntu-system- service (Ubuntu) ** Changed in: ubuntu-system-service (Ubuntu) Assignee: Rodrigo Moya (rodrigo-moya) => (unassigned) -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-control-center in Ubuntu. https://bugs.launchpad.net/bugs/877088 Title: Network proxy setting does not set apt.conf from the second time Status in “ubuntu-system-service” package in Ubuntu: Confirmed Bug description: How to reproduce: 1. open network settings in gnome-control-center 2. set proxy like the example below: * method - manual * HTTP Proxy - example.com:8080 * HTTPS Proxy - example.com:8090 3. press "Apply system wide" - confirm proxy settings are written in /etc/environment and /etc/apt/apt.conf 4. turn off proxy by set back the Method to "None" and press "Apply system wide" again. - confirm proxy settings are gone from /etc/environment and /etc/apt/apt.conf 5. set proxy again as well as step. 2, then press "Apply system wide" again. Expected to happen: 6. proxy settings are written in /etc/environment and /etc/apt/apt.conf What happened instead: 6. proxy settings are written in only /etc/environment, then /etc/apt/apt.conf remains as blank. ProblemType: Bug DistroRelease: Ubuntu 11.10 Package: gnome-control-center 1:3.2.0-0ubuntu6 ProcVersionSignature: Ubuntu 3.0.0-12.20-generic 3.0.4 Uname: Linux 3.0.0-12-generic x86_64 ApportVersion: 1.23-0ubuntu3 Architecture: amd64 CasperVersion: 1.285 Date: Tue Oct 18 05:07:00 2011 LiveMediaBuild: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111011) ProcEnviron: LANG=en_US.UTF-8 SHELL=/bin/bash SourcePackage: gnome-control-center UpgradeStatus: No upgrade log present (probably fresh install) usr_lib_gnome-control-center: deja-dup 20.0-0ubuntu3 gnome-bluetooth 3.2.0-0ubuntu1 indicator-datetime 0.3.0-0ubuntu3 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-system-service/+bug/877088/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp