OnClickListener() must override a superclass method?

With this code:

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
. . .

Button buttonAuthorizeUsers = (Button) findViewById(R.id.buttonAuthorizeUsers);
    buttonAuthorizeUsers.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent configure = new  Intent(OnDemandAndAutomatic_Activity.this, Configure_Activity.class);  
            OnDemandAndAutomatic_Activity.this.startActivity(configure); 
        }
      });

I'm getting:

The method onClick(View) of type new View.OnClickListener(){} must override a superclass method

It would seem that this problem is sometimes caused by a Project | Properties | Java Compiler being set to 1.5.

Although I'm virtually I'd had this problem before, and changed it to 1.6, somehow it WAS 1.5 again.

HOWEVER, that (changing it to 1.6) did not solve the problem. I'm still getting that same err msg, after cleaning, building, and F11ing...???