diff --git a/src/preferences/media/Jamfile b/src/preferences/media/Jamfile
index a98fd6dc21..6c70d3437d 100644
--- a/src/preferences/media/Jamfile
+++ b/src/preferences/media/Jamfile
@@ -2,7 +2,7 @@ SubDir HAIKU_TOP src preferences media ;
 
 SetSubDirSupportedPlatformsBeOSCompatible ;
 
-if $(TARGET_PLATFORM_HAIKU_COMPATIBLE) {
+if ! $(TARGET_PLATFORM_HAIKU_COMPATIBLE) {
 	SubDirC++Flags -fmultiple-symbol-spaces ;
 }