Here is my calculator for kindle 3, signed with the keys from Snake kindlet http://code.google.com/p/snake-game-kindlet/
. so if you've already installed this game, you don't need to worry about the signature problem.
1. download the attachment
2. unzip it, you'll see two files: kcalc.azw2 and developer.keystore.
connect your kindle to your computer with usb cable, copy kcalc.azw2 to the directory "documents"
copy developer.keystore to /var/local/java/keystore/, if you didn't installed it before
3. unplug your kindle from your computer, you'll see "Kalculator" at your home page.
1. install python
2. path_to_your_python waf configure
3. path_to_your_python waf build
the binary would be sitting build/