Canonical announced a few hours ago, December 15th, that it will remove all Sun JDK (Java Development Kit) packages from the Canonical Partner repository.
Because Oracle retired the "Operating System Distributor License for Java", Canonical no longer has permission to redistribute new Java packages.
Therefore, in the near future, Canonical will push empty packages to the repositories, removing Sun JDK from user's machines through the usual update process.
Canonical also suggest that all users have to migrate to OpenJDK as soon as possible, in order to avoid system failures. Installing icedtea6-plugin for the web browser, and openjdk-6-jdk or openjdk-6-jre for the virtual machine will solve the problem.
"Due to the severity of the security risk, Canonical is immediately releasing a security update for the Sun JDK browser plugin which will disable the plugin on all machines. This will mitigate users' risk from malicious websites exploiting the vulnerable version of the Sun JDK." - said Marc Deslauriers from Canonical in the security announcement.