(keitai-l) mitsubishi compatibility?

 Hello all, I have tested this code on two i-mode phones and it works. But
 when I test it on a Mitsubishi, the keys are not responding. Does anybody
 know the reason why this happens? Thanks very much.

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 import com.nttdocomo.io.*;
 import com.nttdocomo.ui.*;
 import com.nttdocomo.util.*;
 import javax.microedition.io.*;
 import java.util.*;
 import java.io.*;
 import java.lang.*;

 public class componentes extends Panel implements ComponentListener{

   Button btOK;
   Label etiqueta;
   TextBox cajaTexto;

   public componentes() {
     etiqueta = new Label("This is a test",Label.CENTER);
     add(etiqueta);

     cajaTexto = new TextBox("",50,1,TextBox.DISPLAY_ANY);
     add(cajaTexto);

     btOK = new Button("OK");
     add(btOK);

     setComponentListener(this);
   }

   public void componentAction(Component source,int type,int param){
     if (type == ComponentListener.BUTTON_PRESSED)
       IApplication.getCurrentApp().terminate();
   }

   public void ejecuta()
   {
     while (true)
     {}


   }
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 import com.nttdocomo.ui.IApplication;
 import com.nttdocomo.ui.Display;

 public class panel extends IApplication{

   public void start()
   {
     componentes misComponentes = new componentes();
     Display.setCurrent(misComponentes);

     misComponentes.ejecuta();
   }

 }
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