I have just followed this tutorial:

https://developers.google.com/drive/quickstart-android

so I don't see a reason for duplicated libs in my project.

I have added the drive Client lib via Google plugin for eclipse

When I build my android app with this manifest

<uses-sdk
    android:minSdkVersion="15"
    android:targetSdkVersion="16" />

<uses-permission android:name="android.permission.READ_CALENDAR" />
<uses-permission android:name="android.permission.WRITE_CALENDAR" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.GET_ACCOUNTS"/>
<uses-permission android:name="android.permission.INTERNET" />

<application
    android:icon="@drawable/todo"
    android:label="@string/app_name" >
    <activity
        android:name=".TodosOverviewActivity"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity
        android:name=".TodoDetailActivity"
        android:windowSoftInputMode="stateVisible|adjustResize" >
        <intent-filter>
            <action android:name="android.intent.action.SEND" />
            <category android:name="android.intent.category.DEFAULT" />
            <data android:mimeType="image/*" />
        </intent-filter>
    </activity>
    <provider
        android:name=".contentprovider.MyTodoContentProvider"
        android:authorities="de.vogella.android.todos.contentprovider" >
    </provider>
</application>

I get the following error:

[2013-10-27 00:43:58 - Dex Loader] Unable to execute dex: Multiple dex files define Lcom/google/api/client/auth/oauth/AbstractOAuthGetToken; [2013-10-27 00:43:58 - de.vogella.android.todos] Conversion to Dalvik format failed: Unable to execute dex: Multiple dex files define Lcom/google/api/client/auth/oauth/AbstractOAuthGetToken;

how can I fix this?