diff --git a/src/backends/qalculate/CMakeLists.txt b/src/backends/qalculate/CMakeLists.txt
--- a/src/backends/qalculate/CMakeLists.txt
+++ b/src/backends/qalculate/CMakeLists.txt
@@ -22,6 +22,10 @@
 
 add_backend(qalculatebackend ${QalculateBackend_SRCS})
 
-target_link_libraries( cantor_qalculatebackend cantorlibs ${QALCULATE_LIBRARIES} )
+if (QALCULATE_VERSION VERSION_LESS 2.0.0)
+    target_link_libraries( cantor_qalculatebackend cantorlibs ${QALCULATE_LIBRARIES} ${CLN_LIBRARIES})
+else()
+    target_link_libraries( cantor_qalculatebackend cantorlibs ${QALCULATE_LIBRARIES})
+endif()
 
 install( FILES cantor_qalculate.knsrc  DESTINATION  ${KDE_INSTALL_CONFDIR} )