diff --git a/mozilla/extensions/auth/Makefile.in b/mozilla/extensions/auth/Makefile.in
index 4437880e83a..c9e3e44e767 100644
--- a/mozilla/extensions/auth/Makefile.in
+++ b/mozilla/extensions/auth/Makefile.in
@@ -50,6 +50,7 @@ include $(DEPTH)/config/autoconf.mk
 MODULE		= negotiateauth
 LIBRARY_NAME	= negotiateauth
 IS_COMPONENT	= 1
+MOZILLA_INTERNAL_API = 1
 
 REQUIRES	= \
 		xpcom \