diff --git a/configure.ac b/configure.ac
index 14f9ef2..a366eff 100644
--- a/configure.ac
+++ b/configure.ac
@@ -57,7 +57,7 @@ AC_CHECK_LIB([crypto], [DES_ecb_encrypt], [], [AC_MSG_ERROR([Cannot find libcryp
 AC_CHECK_HEADER([openssl/des.h], [], [AC_MSG_ERROR([Cannot find openssl headers.])])
 
 # Checks for pkg-config modules.
-LIBNFC_REQUIRED_VERSION=1.3.9
+LIBNFC_REQUIRED_VERSION="1.4.0"
 PKG_CHECK_MODULES([LIBNFC], [libnfc >= $LIBNFC_REQUIRED_VERSION], [], [AC_MSG_ERROR([libnfc >= $LIBNFC_REQUIRED_VERSION is mandatory.])])
 
 PKG_CONFIG_REQUIRES="libnfc"
diff --git a/libfreefare/mifare_desfire_authenticate.c b/libfreefare/mifare_desfire_authenticate.c
index 146e781..04380a9 100644
--- a/libfreefare/mifare_desfire_authenticate.c
+++ b/libfreefare/mifare_desfire_authenticate.c
@@ -142,7 +142,7 @@ mifare_cryto_preprocess_data (MifareTag tag, void *data, size_t *nbytes, int com
 	// Fill in the crypto buffer with data ...
 	memcpy (res, data, *nbytes);
 	// ... CRC ...
-	append_iso14443a_crc (res, *nbytes);
+	iso14443a_crc_append (res, *nbytes);
 	// ... and 0 padding
 	bzero ((uint8_t *)(res) + *nbytes + 2, edl - *nbytes - 2);