diff --git a/src/gsm/Makefile.am b/src/gsm/Makefile.am
index 798f11a..cff089b 100644
--- a/src/gsm/Makefile.am
+++ b/src/gsm/Makefile.am
@@ -26,7 +26,7 @@
 			gprs_cipher_core.c gprs_rlc.c gsm0480.c abis_nm.c gsm0502.c \
 			gsm0411_utils.c gsm0411_smc.c gsm0411_smr.c gsm0414.c \
 			lapdm.c kasumi.c gsm29205.c gsm_04_08_gprs.c \
-			auth_core.c auth_comp128v1.c auth_comp128v23.c auth_xor.c \
+			auth_core.c auth_comp128v1.c auth_comp128v23.c auth_xor.c auth_xor_2g.c \
 			auth_milenage.c milenage/aes-encblock.c gea.c \
 			milenage/aes-internal.c milenage/aes-internal-enc.c \
 			milenage/milenage.c gan.c ipa.c gsm0341.c apn.c \