CUDA external class linkage and unresolved extern function in ptxas file

I'm working with CUDA and I have created an int2_ class to deal with complex integer numbers.

Class declarations in the ComplexTypes.h file as follows:

namespace LibraryNameSpace
{
    class int2_ {

        public:
            int x;
            int y;

            // Constructors
            __host__ __device__ int2_(const int,const int);
            __host__ __device__ int2_();
            // etc.

            // Equalities with other types      
            __host__ __device__ const int2_& operator=(const int);
            __host__ __device__ const int2_& operator=(const float);
            // etc.

    };
}

Class implementations in the ComplexTypes.cpp file as follows:

#include "ComplexTypes.h"

__host__ __device__         LibraryNameSpace::int2_::int2_(const int x_,const int y_)           { x=x_; y=y_;}
__host__ __device__         LibraryNameSpace::int2_::int2_() {}
// etc.

__host__ __device__ const   LibraryNameSpace::int2_& LibraryNameSpace::int2_::operator=(const int a)                        { x = a;            y = 0.;             return *this; }
__host__ __device__ const   LibraryNameSpace::int2_& LibraryNameSpace::int2_::operator=(const float a)                      { x = (int)a;       y = 0.;             return *this; }
// etc.

Everything works well. In the main (which includes ComplexTypes.h) I could deal with int2_ numbers.

In the CudaMatrix.cu file, I'm now including ComplexTypes.h and defining and properly instantiating the __global__ function:

template <class T1, class T2>
__global__ void evaluation_matrix(T1* data_, T2* ob, int NumElements)
{
    const int i = blockDim.x * blockIdx.x + threadIdx.x;
    if(i < NumElements) data_[i] = ob[i];
}

template __global__ void evaluation_matrix(LibraryNameSpace::in