diff --git a/include/objidl.idl b/include/objidl.idl
index 2aa606579d6f6f1eb7e8c543ec0fcaca0b7dd8a5..95f4b9f5a07ad2a26aef755247692b39c9959e4d 100644
--- a/include/objidl.idl
+++ b/include/objidl.idl
@@ -1950,6 +1950,9 @@ interface IClientSecurity : IUnknown
     void *pAuthInfo;
   } SOLE_AUTHENTICATION_INFO;
 
+  const OLECHAR *COLE_DEFAULT_PRINCIPAL = /*(OLECHAR*)*/ -1;
+  const void *COLE_DEFAULT_AUTHINFO = /*(void*)*/ -1;
+
   typedef struct tagSOLE_AUTHENTICATION_LIST {
     DWORD cAuthInfo;
     SOLE_AUTHENTICATION_INFO *aAuthInfo;