diff --git a/src/dbus/qdbusextratypes.h b/src/dbus/qdbusextratypes.h
index 793ef3191b..0127223fe8 100644
--- a/src/dbus/qdbusextratypes.h
+++ b/src/dbus/qdbusextratypes.h
@@ -95,7 +95,7 @@ inline bool operator!=(const QDBusObjectPath &lhs, const QDBusObjectPath &rhs)
 inline bool operator<(const QDBusObjectPath &lhs, const QDBusObjectPath &rhs)
 { return lhs.path() < rhs.path(); }
 
-inline uint qHash(const QDBusObjectPath &objectPath, uint seed)
+inline uint qHash(const QDBusObjectPath &objectPath, uint seed = 0)
 { return qHash(objectPath.path(), seed); }
 
 
@@ -145,7 +145,7 @@ inline bool operator!=(const QDBusSignature &lhs, const QDBusSignature &rhs)
 inline bool operator<(const QDBusSignature &lhs, const QDBusSignature &rhs)
 { return lhs.signature() < rhs.signature(); }
 
-inline uint qHash(const QDBusSignature &signature, uint seed)
+inline uint qHash(const QDBusSignature &signature, uint seed = 0)
 { return qHash(signature.signature(), seed); }
 
 class QDBusVariant