--- CMakeLists.txt.orig	2017-04-17 14:19:04 UTC
+++ CMakeLists.txt
@@ -73,6 +73,7 @@ if(QT5_BUILD)
 else()
   find_package(Qt4 REQUIRED)
   find_package(QJSON 0.8.0 REQUIRED)
+  include_directories(${QJSON_INCLUDE_DIR})
   include(${QT_USE_FILE})
 endif()
 
