-r:System.ServiceModel.Web.dll \
-r:System.Data.Services.Client.dll
+ifeq (4, $(FRAMEWORK_VERSION_MAJOR))
+LIB_MCS_FLAGS += -r:System.ServiceModel.Activation.dll
+endif
+
TEST_MCS_FLAGS = -r:System.ServiceModel.dll -r:System.Core.dll
include ../../build/library.make