Display message after Package install

I developed a Android-Homescreen-Widget and got a weird problem: The "Open"-Button in the Market grayed out because there is actually no Application to launch. So, many people complain because they don't realize that my package is a widget. They even give me a bad rating and I want to avoid that by giving the people a hint what they should do. A first-line-hint in the description (written in Uppercase) didn't help at all, so I'm searching for a better solution.

Is it possible to display a message directly after the installation of 开发者_运维问答a package in the android-market?

The best solution I could find is to create a new Activity, and add an intent-filter like this:

        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.INFO" />
        </intent-filter>

This does not create a icon in the launcher but makes the Open-Button in the Market active and the Activity gets launched when clicked.

Apps like BeautifulWidget make an application that you can launch that just shows instructions on how to install the Widget. A waste of space, but some people out there really just don't understand widgets without hand holding.