Android application error on starting new activity

I'm having a problem in my Android 1.6 app. I have a two java class files, each with their corresponding XML layout file.

When I perform the following:

Intent ii = new Intent(this,
           PatientEntry.class);
startActivity(ii);

I get an application error:

Sorry! The appl开发者_运维技巧ication XXXX has stopped unexpectedly. Please try again.

I have added the following to my AndroidManifest.xml file:

<activity android:name=".PatientEntry"
          android:label="@string/app_name">
</activity>

Why am I getting these errors and how do I fix it?

Thanks, Mike

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Make sure to add PatientEntry activity to your manifest file.

<activity android:name=".PatientEntry"></activity>

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May be there are problems in PatientEntry class. If you give the logcat with the error specified then guess we can help.