diff --git a/lib/gssapi/Makefile.am b/lib/gssapi/Makefile.am
index 96f6210b5..c71aacdce 100644
--- a/lib/gssapi/Makefile.am
+++ b/lib/gssapi/Makefile.am
@@ -156,6 +156,7 @@ ntlmsrc = \
 	ntlm/export_sec_context.c \
 	ntlm/external.c \
 	ntlm/ntlm.h \
+	ntlm/ntlm-private.h \
 	ntlm/import_name.c \
 	ntlm/import_sec_context.c \
 	ntlm/indicate_mechs.c \