Package 'sun-java6-jdk' has no installation candidate

http://happy-coding.com/install-sun-java6-jdk-on-ubuntu-10-04-lucid/
I just had trouble to install the Sun Java6 JDK after updating to Ubuntu 10.04. The problem was that the system couldn’t find the package sun-java6-sdk and apt-get gave me the message:

Package sun-java6-jdk is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package sun-java6-jdk has no installation candidate

What I did to solve this problem was to add a new source

sudo add-apt-repository "deb http://archive.canonical.com/ lucid partner"
After that a normal

sudo apt-get update
sudo apt-get install sun-java6-jdk
it worked for me.

安装openssl时找不到ssl.h时的解决办法
ruby extconf.rb --with-openssl-include=/usr/local/ssl/include/ --with-openssl-lib=/usr/local/ssl/lib