problem with Excel.AppEvents_SheetActivateEventHandler'

Code:

using System;
using System.Collections.Generic;
using System.Text;
using Excel = Microsoft.Office.Interop.Excel;
using System.Windows.Forms;

namespace ConsoleApplicationProva1
{
    class Program
    {
        static void Main(string[] args)
        {
            Excel.Application thisApplication = new Excel.Application();
            thisApplication.Visible = true;
            thisApplication.StatusBar = "Enor";
            thisApplication.Workbooks.Add(System.Type.Missing);
            //
            thisApplication.SheetActivate += new Excel.AppEvents_SheetActivateEventHandler(thisApplication_SheetActivate);
        }

        void thisApplication_SheetActivate(object sender, Excel.Range target, ref bool cancel)
        {
            MessageBox.Show("Enor");
        }
    }
}

This code wich I found in e book fires error like below
Error 1 No overload for 'thisApplication_SheetActivate' matches delegate 'Microsoft.Office.Interop.Excel.AppEvents_SheetActivateEventHandler' C:\Documents and Settings\Enor\My Documents\Visual Studio 2008\Projects\ConsoleApplicationProva1\ConsoleApplicationProva1\Program.cs 19 46 ConsoleApplicationProva1
does anybody know how to deal with this?
Thakns in advance