Doesn't work at all for me. Standard install of 32-bit karmic, added Eclipse (which brings in a lot of the development stuff), and the "android" tool fails to download any platforms or add-ons. When checking the "force http" option and pressing the "save & apply" button, the button stays down and the program hangs.
I suspected it might have something to do with the fact that Karmic uses OpenJDK by default, so I completely removed OpenJDK and installed Sun Java 6. "java -version" confirms that Sun's is the one being run. Exactly the same result. Running "android --verbose" give no help at all.
I suspect that there's some other development tools needed that aren't listed in in the Android SDK's system requirements. If I may ask, which JDK are you running, and what other development packages do you have installed (I installed ant as well)?