JNI4NET - 2 way communication between JAVA and C# both ways

I am trying to use JNI4NET to do two 2 way communication between a JAVA and C#. I have the following super simple C# project:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using jnijavatestapp;

namespace JNICSharpTestApp
{
    public class JNICSharpTest
    {
        public void HelloWorldFromCSharp()
        {
            Console.WriteLine("Hi Java, this is C# talking!!!");
        }

        public void CallBackToJAVA()
        {
            JAVACLASS java = new JAVACLASS();
            java.HelloWorldJAVA();
        }
    }
}

Then my java project has two classes like this:

package jnijavatestapp;
import java.io.IOException;
import jnicsharptestapp.JNICSharpTest;
import net.sf.jni4net.Bridge;

public class JNIJavaTestApp 
{

    public static void main(String[] args) throws IOException {
       InitJNI4Net();
       JNICSharpTest test = new JNICSharpTest();
       test.HelloWorldFromCSharp();
       test.CallBackToJAVA();
    }    

    public static void InitJNI4Net() throws IOException{
        Bridge.init();
        java.io.File file = new java.io.File("..\\COMMON_RESOURCES\\work\\JNICSharpTestApp.j4n.dll");
        Bridge.LoadAndRegisterAssemblyFrom(file);
    }
}

public class JAVACLASS
{
    public void HelloWorldJAVA()    
    {
        System.out.println("Hi C# this is JAVA Talking!!");
    }
}

I am able to get JAVA to call C# but as soon as I try to call test.CallBackToJAVA() it fails.

This is how I am building:

@echo off

cd COMMON_RESOURCES

echo.
echo Running ProxyGen.exe for C#...
..\JNI4NET\bin\proxygen.exe work\JNICSharpTestApp.dll -wd work

echo.
echo Building C#...
cd work
build

@echo off
copy JNI4NET\lib\*.* COMMON_RESOURCES\work /y 
copy JNIJavaTestApp\dist\JNIJavaTestApp.jar COMMON_RESOURCES\work /y 

cd COMMON_RESOURCES

echo.
echo Running ProxyGen.exe for JAVA...
..\JNI4NET\bin\proxygen.exe ..\JNIJavaTestApp\dist\JNIJavaTestApp.jar -wd work

echo.
echo Building JAVA...
cd work
build

Steps:

  1. Build .NET project and copy dll to "work" folder
  2. Generate proxies on the .net project
  3. Run build.bat
  4. Generate proxies on the jvm project 5.Run build.bat

Can't figure-out what I'm doing wrong to get two way coms with JNI4NET and need help!

link to project