How to use Android 4.0 ICS sdk manager on linux behind firewall

I am not 100% sure if there is other ways to use sdk manager on linux for ICS sdk manager.
My tips are:

pre-condition : suppose you have source code of ICS

1. Modify 'sdk/sdkmanager/libs/sdkuilib/src/com/android/sdkuilib/internal/repository/SettingsController.java'
- In 'getForceHttp' method,
return true;
//return Boolean.parseBoolean(mProperties.getProperty(ISettingsPage.KEY_FORCE_HTTP));

2. 'sdk/sdkmanager/libs/sdklib/src/com/android/sdklib/internal/repository/UrlOpener.java'
- In 'openWithHttpClient' method
add 2 lines of import..

import org.apache.http.conn.params.ConnRoutePNames;
import org.apache.http.HttpHost;

and modify like below

// use the simple one
final DefaultHttpClient httpClient = new DefaultHttpClient();

// newly added
HttpHost proxy = new HttpHost("{proxy address}", {proxy port});
httpClient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy);