diff --git a/CMake/variants/variants.fs5 b/CMake/variants/variants.fs5
index caed8cc1c9083235f3f539158d6db1b727431fd5..ba3781b2d208bfbec2a33c9065a6c48aca7e1045 100644
--- a/CMake/variants/variants.fs5
+++ b/CMake/variants/variants.fs5
@@ -13,12 +13,13 @@
 # Define build variants.
 #list(APPEND LOFAR_BUILD_VARIANTS CN ION)
 
-set(GNU_CXX_FLAGS "-W -Wall -Woverloaded-virtual -Wno-unknown-pragmas -fopenmp -DCLUSTER_SCHEDULING")
+set(GNU_CXX_FLAGS "-W -Wall -Woverloaded-virtual -Wno-unknown-pragmas -DCLUSTER_SCHEDULING")
 
 # Options
 option(USE_HDF5      "Use HDF5"      OFF)
 option(USE_LOG4CPLUS            "Use Log4Cplus"               OFF)
 option(USE_MPI                  "Use MPI"                     ON)
+option(USE_OPENMP               "Use OpenMP"                  ON)
 option(USE_PQXX                 "Use libpqxx"                 OFF)
 
 # Host specific paths to third party packages
diff --git a/RTCP/InputProc/CMakeLists.txt b/RTCP/InputProc/CMakeLists.txt
index 18ab5405e0d2971349d32a5fde59c26b876fef46..9959d91d23ffbe7591850aa2a55e6dcfb2fa85da 100644
--- a/RTCP/InputProc/CMakeLists.txt
+++ b/RTCP/InputProc/CMakeLists.txt
@@ -5,7 +5,7 @@ lofar_package(InputProc 1.0
 
 include(LofarFindPackage)
 lofar_find_package(Boost REQUIRED COMPONENTS date_time)
-#lofar_find_package(Libssh2)
+lofar_find_package(OpenMP REQUIRED)
 #lofar_find_package(Valgrind)
 #lofar_find_package(Casacore COMPONENTS measures REQUIRED)