Ubuntu 11.10更改源方法：
用Ctrl+Alt+T打开终端：
输入命令：sudo gedit /etc/apt/sources.list //打开软件源列表，将下面源复制进去，放在文件开头，保存退出。
sudo apt-get update //更新源列表
sudo apt-get upgrade //这一步是更新软件
中科大的ipv6源：
#ustc
deb http://debian.ustc.edu.cn/ubuntu/ oneiric main restricted universe multiverse
deb http://debian.ustc.edu.cn/ubuntu/ oneiric-backports restricted universe multiverse
deb http://debian.ustc.edu.cn/ubuntu/ oneiric-proposed main restricted universe multiverse
deb http://debian.ustc.edu.cn/ubuntu/ oneiric-security main restricted universe multiverse
deb http://debian.ustc.edu.cn/ubuntu/ oneiric-updates main restricted universe multiverse
deb-src http://debian.ustc.edu.cn/ubuntu/ oneiric main restricted universe multiverse
deb-src http://debian.ustc.edu.cn/ubuntu/ oneiric-backports main restricted universe multiverse
deb-src http://debian.ustc.edu.cn/ubuntu/ oneiric-proposed main restricted universe multiverse
deb-src http://debian.ustc.edu.cn/ubuntu/ oneiric-security main restricted universe multiverse
deb-src http://debian.ustc.edu.cn/ubuntu/ oneiric-updates main restricted universe multiverse