diff --git a/components/nif/property.hpp b/components/nif/property.hpp
index b06044e9f0..2633b16c59 100644
--- a/components/nif/property.hpp
+++ b/components/nif/property.hpp
@@ -33,7 +33,7 @@ class Property : public Named
 {
 public:
     // The meaning of these depends on the actual property type.
-    int flags;
+    unsigned int flags;
 
     void read(NIFStream *nif);
 };