I use ipp 6.0, windows 64, last lats opencv 2.4 from github
at build I have following errors:

.....\modules\core\src\dxt.cpp(1564) : error C2065: 'ippsDFTGetSize_R_32f' : undeclared identifier
5>......\modules\core\src\dxt.cpp(1565) : error C2065: 'ippsDFTInit_R_32f' : undeclared identifier
5>......\modules\core\src\dxt.cpp(1569) : error C2065: 'ippsDFTGetSize_R_64f' : undeclared identifier
5>......\modules\core\src\dxt.cpp(1570) : error C2065: 'ippsDFTInit_R_64f' : undeclared identifier
5>......\modules\core\src\dxt.cpp(1577) : error C2065: 'ippsDFTGetSize_C_32fc' : undeclared identifier
5>......\modules\core\src\dxt.cpp(1578) : error C2065: 'ippsDFTInit_C_32fc' : undeclared identifier 7>tif_tile.c
5>......\modules\core\src\dxt.cpp(1582) : error C2065: 'ippsDFTGetSize_C_64fc' : undeclared identifier
5>......\modules\core\src\dxt.cpp(1583) : error C2065: 'ippsDFTInit_C_64fc' : undeclared identifier