diff --git a/unsupported/test/CMakeLists.txt b/unsupported/test/CMakeLists.txt
index 23217811f..f42077bdc 100644
--- a/unsupported/test/CMakeLists.txt
+++ b/unsupported/test/CMakeLists.txt
@@ -23,6 +23,6 @@ ei_add_test(FFT)
 
 find_package(FFTW)
 if(FFTW_FOUND)
-  ei_add_test(FFTW  " " "${FFTW_LIBRARIES}" )
+  ei_add_test(FFTW  " " "-lfftw3 -lfftw3f -lfftw3l" )
 endif(FFTW_FOUND)
 
diff --git a/unsupported/test/FFTW.cpp b/unsupported/test/FFTW.cpp
new file mode 100644
index 000000000..cf7be75aa
--- /dev/null
+++ b/unsupported/test/FFTW.cpp
@@ -0,0 +1,136 @@
+// This file is part of Eigen, a lightweight C++ template library
+// for linear algebra. Eigen itself is part of the KDE project.
+//
+// Copyright (C) 2009 Mark Borgerding mark a borgerding net
+//
+// Eigen is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; either
+// version 3 of the License, or (at your option) any later version.
+//
+// Alternatively, you can redistribute it and/or
+// modify it under the terms of the GNU General Public License as
+// published by the Free Software Foundation; either version 2 of
+// the License, or (at your option) any later version.
+//
+// Eigen is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+// FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License or the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License and a copy of the GNU General Public License along with
+// Eigen. If not, see <http://www.gnu.org/licenses/>.
+
+#include "main.h"
+#include <fftw3.h>
+#include <unsupported/Eigen/FFT>
+
+using namespace std;
+
+float norm(float x) {return x*x;}
+double norm(double x) {return x*x;}
+long double norm(long double x) {return x*x;}
+
+template < typename T>
+complex<long double>  promote(complex<T> x) { return complex<long double>(x.real(),x.imag()); }
+
+complex<long double>  promote(float x) { return complex<long double>( x); }
+complex<long double>  promote(double x) { return complex<long double>( x); }
+complex<long double>  promote(long double x) { return complex<long double>( x); }
+    
+
+    template <typename T1,typename T2>
+    long double fft_rmse( const vector<T1> & fftbuf,const vector<T2> & timebuf)
+    {
+        long double totalpower=0;
+        long double difpower=0;
+        cerr <<"idx\ttruth\t\tvalue\t|dif|=\n";
+        for (size_t k0=0;k0<fftbuf.size();++k0) {
+            complex<long double> acc = 0;
+            long double phinc = -2.*k0* M_PIl / timebuf.size();
+            for (size_t k1=0;k1<timebuf.size();++k1) {
+                acc +=  promote( timebuf[k1] ) * exp( complex<long double>(0,k1*phinc) );
+            }
+            totalpower += norm(acc);
+            complex<long double> x = promote(fftbuf[k0]); 
+            complex<long double> dif = acc - x;
+            difpower += norm(dif);
+            cerr << k0 << "\t" << acc << "\t" <<  x << "\t" << sqrt(norm(dif)) << endl;
+        }
+        cerr << "rmse:" << sqrt(difpower/totalpower) << endl;
+        return sqrt(difpower/totalpower);
+    }
+
+    template <typename T1,typename T2>
+    long double dif_rmse( const vector<T1> buf1,const vector<T2> buf2)
+    {
+        long double totalpower=0;
+        long double difpower=0;
+        size_t n = min( buf1.size(),buf2.size() );
+        for (size_t k=0;k<n;++k) {
+            totalpower += (norm( buf1[k] ) + norm(buf2[k]) )/2.;
+            difpower += norm(buf1[k] - buf2[k]);
+        }
+        return sqrt(difpower/totalpower);
+    }
+
+template <class T>
+void test_scalar(int nfft)
+{
+    typedef typename Eigen::FFT<T>::Complex Complex;
+    typedef typename Eigen::FFT<T>::Scalar Scalar;
+
+    FFT<T> fft;
+    vector<Scalar> inbuf(nfft);
+    vector<Complex> outbuf;
+    for (int k=0;k<nfft;++k)
+        inbuf[k]= (T)(rand()/(double)RAND_MAX - .5);
+    fft.fwd( outbuf,inbuf);
+    VERIFY( fft_rmse(outbuf,inbuf) < test_precision<T>()  );// gross check
+
+    vector<Scalar> buf3;
+    fft.inv( buf3 , outbuf);
+    VERIFY( dif_rmse(inbuf,buf3) < test_precision<T>()  );// gross check
+}
+
+template <class T>
+void test_complex(int nfft)
+{
+    typedef typename Eigen::FFT<T>::Complex Complex;
+
+    FFT<T> fft;
+
+    vector<Complex> inbuf(nfft);
+    vector<Complex> outbuf;
+    vector<Complex> buf3;
+    for (int k=0;k<nfft;++k)
+        inbuf[k]= Complex( (T)(rand()/(double)RAND_MAX - .5), (T)(rand()/(double)RAND_MAX - .5) );
+    fft.fwd( outbuf , inbuf);
+
+    VERIFY( fft_rmse(outbuf,inbuf) < test_precision<T>()  );// gross check
+
+    fft.inv( buf3 , outbuf);
+
+    VERIFY( dif_rmse(inbuf,buf3) < test_precision<T>()  );// gross check
+}
+
+void test_FFTW()
+{
+
+  CALL_SUBTEST( test_complex<float>(32) ); CALL_SUBTEST( test_complex<double>(32) ); CALL_SUBTEST( test_complex<long double>(32) );
+  CALL_SUBTEST( test_complex<float>(256) ); CALL_SUBTEST( test_complex<double>(256) ); CALL_SUBTEST( test_complex<long double>(256) );
+  CALL_SUBTEST( test_complex<float>(3*8) ); CALL_SUBTEST( test_complex<double>(3*8) ); CALL_SUBTEST( test_complex<long double>(3*8) );
+  CALL_SUBTEST( test_complex<float>(5*32) ); CALL_SUBTEST( test_complex<double>(5*32) ); CALL_SUBTEST( test_complex<long double>(5*32) );
+  CALL_SUBTEST( test_complex<float>(2*3*4) ); CALL_SUBTEST( test_complex<double>(2*3*4) ); CALL_SUBTEST( test_complex<long double>(2*3*4) );
+  CALL_SUBTEST( test_complex<float>(2*3*4*5) ); CALL_SUBTEST( test_complex<double>(2*3*4*5) ); CALL_SUBTEST( test_complex<long double>(2*3*4*5) );
+  CALL_SUBTEST( test_complex<float>(2*3*4*5*7) ); CALL_SUBTEST( test_complex<double>(2*3*4*5*7) ); CALL_SUBTEST( test_complex<long double>(2*3*4*5*7) );
+
+
+
+  CALL_SUBTEST( test_scalar<float>(32) ); CALL_SUBTEST( test_scalar<double>(32) ); CALL_SUBTEST( test_scalar<long double>(32) );
+  CALL_SUBTEST( test_scalar<float>(45) ); CALL_SUBTEST( test_scalar<double>(45) ); CALL_SUBTEST( test_scalar<long double>(45) );
+  CALL_SUBTEST( test_scalar<float>(50) ); CALL_SUBTEST( test_scalar<double>(50) ); CALL_SUBTEST( test_scalar<long double>(50) );
+  CALL_SUBTEST( test_scalar<float>(256) ); CALL_SUBTEST( test_scalar<double>(256) ); CALL_SUBTEST( test_scalar<long double>(256) );
+  CALL_SUBTEST( test_scalar<float>(2*3*4*5*7) ); CALL_SUBTEST( test_scalar<double>(2*3*4*5*7) ); CALL_SUBTEST( test_scalar<long double>(2*3*4*5*7) );
+}