diff --git a/CMakeLists.txt b/CMakeLists.txt
index 61bfe0ec6e09628a568fceb088b1064a6e83e716..a0516fe5c8f6d015b0b02b589861092d22ca5dd9 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -402,10 +402,6 @@ 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)