Ubuntu 9.10以上版本中，Ubuntu去除了對sun-java5-jdk的支持，如果必須安裝sun-java5-jdk。那么可以采用如下方法：
1.編輯/etc/apt/sources.list文件，將安裝源更改為Ubuntu 9.04的安裝源為：
deb http://archive.Ubuntu.com/ubuntu/ jaunty main restricted universe multiverse
deb http://archive.Ubuntu.com/ubuntu/ jaunty-security main restricted universe multiverse
deb http://archive.Ubuntu.com/ubuntu/ jaunty-updates main restricted universe multiverse
deb http://archive.Ubuntu.com/ubuntu/ jaunty-proposed main restricted universe multiverse
deb http://archive.Ubuntu.com/ubuntu/ jaunty-backports main restricted universe multiverse
deb-src http://archive.Ubuntu.com/ubuntu/ jaunty main restricted universe multiverse
deb-src http://archive.Ubuntu.com/ubuntu/ jaunty-security main restricted universe multiverse
deb-src http://archive.Ubuntu.com/ubuntu/ jaunty-updates main restricted universe multiverse
deb-src http://archive.Ubuntu.com/ubuntu/ jaunty-proposed main restricted universe multiverse
2. sudo apt-get install sun-java5-jdk