Wrong working of Button.MouseLeave in Windows XP .NET 1.1

using System;

using System.Windows.Forms;

using wx;

using System.Drawing;

using Button = wx.Button;

 

namespace wxNET

{

 

      class MyFrame : Frame

      {

            public MyFrame(string title): base(title!= null?title:"oops...")

            {

 

                  

            }

      }

 

      

 

      class Start : App

      {

            public override bool OnInit()

            {

                  MyFrame frame = new MyFrame("princed");

                  Button but = new Button(frame,"Press");

                  //but.SetSize(new Size(10,12));

 

                  but.Click+= new EventListener(ButtonPressHandler);

 

                  but.MouseLeave+= new EventListener(but_MouseLeave);

                  return frame.Show();

 

 

            }

 

            public static void ButtonPressHandler(object sender, Event e)

            {

                  

                  MessageDialog.ShowModal("message","Caption",1);

            }

 

            [STAThread]

            static void Main(string[] args)

            {

                  Start s = new Start();

                  s.Run();

            }

 

            private void but_MouseLeave(object sender, Event e)

            {

                  MessageDialog.ShowModal("Mouse left","Caption",1);

 

            }

      }

}

 

 

NOTE:

 When I move the mouse very fast over the button which fills the entire
frame (MyFrame), MouseLeave(but_MouseLeave) is not getting called ....and
after this fast move , MouseLeave(but_MouseLeave) is getting called on mouse
enter !!!!!!