migration to vaadin 8 - problem with Widgetset

Hi,
I'm migrating my application from 7 to 8, following the documentation. Here the steps I followed:
I changed the maven dependancies, using the compatibility artifact:

<dependency>
    <groupId>com.vaadin</groupId>
    <artifactId>vaadin-compatibility-server</artifactId>
    <version>8.0.4</version>
</dependency>
<dependency>
    <groupId>com.vaadin</groupId>
    <artifactId>vaadin-compatibility-client-compiled</artifactId>
    <version>8.0.4</version>
</dependency>        
<dependency>
    <groupId>com.vaadin</groupId>
    <artifactId>vaadin-compatibility-client</artifactId>
    <version>8.0.4</version>
    <scope>provided</scope>
</dependency>        

I added to UI the annotation

@Widgetset("com.mydomain.AppWidgetSet")

I recompiled the theme and the Widgetset with no erros.
in AppWidgetSet.gwt.xml, I found:

<inherits name="com.vaadin.v7.Vaadin7WidgetSet" />

Now I can compile the application, but after login, the browser display:

Widgetset 'com.mydomain.AppWidgetSet' does not contain an implementation for com.vaadin.v7.ui.Label. Check the connector's @Connect mapping, the widgetset's GWT module description file and re-compile your widgetset. In case you have downloaded a vaadin add-on package, you might want to refer to add-on instructions.

Where am I wrong?
Thank you, Francesco

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