diff --git a/libs/freetdm/src/Makefile b/libs/freetdm/src/Makefile
index 8e9ba7b093..cd2040f9c5 100644
--- a/libs/freetdm/src/Makefile
+++ b/libs/freetdm/src/Makefile
@@ -51,6 +51,7 @@ isdn/Q931ie.o \
 isdn/Q931mes.o \
 isdn/Q931StateNT.o \
 isdn/Q931StateTE.o \
+isdn/nationalStateNT.o\
 isdn/Q932mes.o 
 
 PWD=$(shell pwd)