Comment 37 for bug 152362

Actually, the instructions that were posted cause apt-get source to rebuild everything four times, because specifying any one of those java packages will build all of them. After installing the dependencies, just run 'apt-get -b source icedtea-java7-jre' (no sudo needed as long as you have fakeroot installed).

And if you've already got the jre package built, go ahead and install it, because that's the only one you need to replace.