Comment 1 for bug 191090

Well, this bug is filed against sun-java6, which should give you a clue.. ;)

Try "update-java-alternatives", on my system (Hardy) it looks like this:
$ update-java-alternatives -l
java-6-sun 63 /usr/lib/jvm/java-6-sun
java-7-icedtea 1060 /usr/lib/jvm/java-7-icedtea
java-gcj 1042 /usr/lib/jvm/java-gcj

Using update-java-alternatives, you can change all java-related links to the given java virtual machine.