Can you change min. API level for your Android app in Eclipse?
If you go into your Manifest file and set
<uses-sdk android:minSdkVersion="3" />
to
<uses-sdk android:minSdkVersion="4" />
Then you will have changed your entire project from running 1.5 as a minimum to 1.6.
While you are still building your app, you can change the minimum API level at any time.