Tell android to start my App when opening files with a specific extension

Question

I've written an App, which only encrypts special files I made and I can't find a way to tell the standard dataexplorer to use my App for opening this extension. This is what my intent-filter currently looks like:

<activity
    android:name="ImportDataActivity" >
    <intent-filter>
        <action android:name="android.intent.action.VIEW" />
        <action android:name="android.intent.action.EDIT" />
        <category android:name="android.intent.category.DEFAULT" />
        <data
            android:mimeType="application/octet-stream"
            android:host="*"
            android:pathPattern=".*\\.mEn"
        />
    </intent-filter>
    <intent-filter>
        <action android:name="android.intent.action.VIEW" />
        <action android:name="android.intent.action.EDIT" />
        <category android:name="android.intent.category.DEFAULT" />
        <data
            android:mimeType="application/.mEn"
            android:host="*" 
            android:pathPattern=".*\\.mEn"
        />
    </intent-filter>
</activity>

How can I make the the standard dataexplorer use my App for opening this extension?