If you have problems to include ActionBarSherlock in your Android project (because of not generated R.java or something) then follow this quick guide:
Include ActionBarSherlock as library in your Eclipse-Workspace.
Both project needs to compile with Android 4.0 or newer. And you must specify a targetSdkVersion of 11 or higher in your application’s manifest .
If you want to develop for Android 2.1 then add this to your application’s manifest and also build your app with api-level 15 (Android 4.0.3)
<uses-sdk android:minSdkVersion="7" android:targetSdkVersion="15"/>
Finally select “Project” -> “Clean” -> “Clean all projects” in Eclipse.