CUDA CUFFT on Shield Tablet

Hey guys, I have tried to modify the CUDA samples on Shield Tablet by using CUFFT. However, when I build the program, I got the link errors:undefined reference to ‘cufftExecR2C’; undefined reference to ‘cufftExecC2R’.

I thought the errors may cause by missing .so file. Then I added the libcufft.so in the
Android.mk file, like:

include (CLEAR_VARS) LOCAL_MODULE := libcufft LOCAL_LIB_PATH += (CUDA_TOOLKIT_ROOT)/targets/armv7-linux-androideabi/lib/
LOCAL_SRC_FILES := (LOCAL_LIB_PATH)/libcufft.so include (PREBUILT_SHARED_LIBRARY)

I still got the same errors. Could anyone please help me and point me to right direction?

Thanks a lot.