Modified /etc/apt/source.list
#sudo vim /etc/apt/source.list
And add following source site for jaunty
deb http://tw.archive.ubuntu.com/ubuntu/ jaunty main restricted universe multiverse
deb-src http://tw.archive.ubuntu.com/ubuntu/ jaunty main restricted universe multiverse #Added by software-properties
Step 2.
Update and Install Sun JDK 1.5.0
#sudo apt-get update && sudo apt-get install sun-java5-jdk
Step 3.
Remove source site for jaunty in source.list
#sudo vim /etc/apt/source.list
Step 4.
Set default java
#sudo update-alternatives --config java
#sudo update-java-alternatives -s java-1.5.0-sun
sudo update-java-alternatives -s java-1.5.0-sun
