If you are having trouble downloading or installing additional SDK’s via the eclipse android sdk manager you might need to update the proxy settings. I tried exporting HTTP_PROXY variable in bash but that didn’t work. Here is what worked for me.
1) Start eclipse
2) In Eclipse open the “Window” menu and choose “Android SDK Manager” item
3) In the Android SDK Manager dialog, Open the Tools menu and choose Options.
4) Enter your proxy address and port. Don’t include the http:// in the proxy address just the server name (e.g. myproxy.mydomain.com).
Finally, From the Android SDK manager dialog refresh the available packages by opening the Packages Menu and choose Reload.