diff --git a/Project.xml b/Project.xml
index a298c919f..74da3b749 100644
--- a/Project.xml
+++ b/Project.xml
@@ -128,7 +128,7 @@
 	<haxeflag name="-w" value="-WDeprecated" />
 
 	<!-- Haxe 4.3.0+: Enable pretty syntax errors and stuff. -->
-	<haxedef name="message-reporting" value="pretty" />
+	<haxedef name="message.reporting" value="pretty" />
 
 	<!-- _________________________________ Custom _______________________________ -->
 	<!-- Disable trace() calls in release builds to bump up performance. -->