diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4b3b62ecd5e428353ffee3810d9bbe67ade8c845..44193cac416331e1537e69d4077cce055fcd57a4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -426,6 +426,10 @@ if (WIN32)
 	ADD_DEFINITIONS(-DBOOST_THREAD_USE_LIB)
 endif()
 
+# We cannot use boost:signals2, because Swiften does not use them,
+# for now, just ignore the deprecation warning.
+ADD_DEFINITIONS(-DBOOST_SIGNALS_NO_DEPRECATION_WARNING)
+
 if(CMAKE_BUILD_TYPE MATCHES Debug)
 	if (CMAKE_COMPILER_IS_GNUCXX)
 		ADD_DEFINITIONS(-O0)