diff --git a/README b/README
index eed54878..6c1bc764 100644
--- a/README
+++ b/README
@@ -15,6 +15,8 @@ Version 0.5
 
   Added ./configure option '--disable-gex-new' to allow using the older group-exchange format
 
+  Added MAC methods hmac-md5 and hmac-md5-96.
+
 Version 0.4
 -----------
 
diff --git a/include/libssh2_priv.h b/include/libssh2_priv.h
index 5138ba34..9f590384 100644
--- a/include/libssh2_priv.h
+++ b/include/libssh2_priv.h
@@ -234,9 +234,6 @@ struct _LIBSSH2_SESSION {
 struct _LIBSSH2_KEX_METHOD {
 	char *name;
 
-	/* integrity key length */
-	unsigned long key_len;
-
 	/* Key exchange, populates session->* and returns 0 on success, non-0 on error */
 	int (*exchange_keys)(LIBSSH2_SESSION *session);
 
@@ -293,6 +290,9 @@ struct _LIBSSH2_MAC_METHOD {
 	/* The length of a given MAC packet */
 	int mac_len;
 
+	/* integrity key length */
+	int key_len;
+
 	/* Message Authentication Code Hashing algo */
 	int (*init)(LIBSSH2_SESSION *session, unsigned char *key, int *free_key, void **abstract);
 	int (*hash)(LIBSSH2_SESSION *session, unsigned char *buf, unsigned long seqno, const unsigned char *packet, unsigned long packet_len, const unsigned char *addtl, unsigned long addtl_len, void **abstract);
diff --git a/src/kex.c b/src/kex.c
index af68d3a5..ca0bb05c 100644
--- a/src/kex.c
+++ b/src/kex.c
@@ -385,11 +385,11 @@ static int libssh2_kex_method_diffie_hellman_groupGP_sha1_key_exchange(LIBSSH2_S
 		unsigned char *key = NULL;
 		int free_key = 0;
 
-		LIBSSH2_KEX_METHOD_DIFFIE_HELLMAN_SHA1_HASH(key, session->kex->key_len, "E");
+		LIBSSH2_KEX_METHOD_DIFFIE_HELLMAN_SHA1_HASH(key, session->local.mac->key_len, "E");
 		session->local.mac->init(session, key, &free_key, &session->local.mac_abstract);
 
 		if (free_key) {
-			memset(key, 0, session->kex->key_len);
+			memset(key, 0, session->local.mac->key_len);
 			LIBSSH2_FREE(session, key);
 		}
 	}
@@ -402,11 +402,11 @@ static int libssh2_kex_method_diffie_hellman_groupGP_sha1_key_exchange(LIBSSH2_S
 		unsigned char *key = NULL;
 		int free_key = 0;
 
-		LIBSSH2_KEX_METHOD_DIFFIE_HELLMAN_SHA1_HASH(key, session->kex->key_len, "F");
+		LIBSSH2_KEX_METHOD_DIFFIE_HELLMAN_SHA1_HASH(key, session->remote.mac->key_len, "F");
 		session->remote.mac->init(session, key, &free_key, &session->remote.mac_abstract);
 
 		if (free_key) {
-			memset(key, 0, session->kex->key_len);
+			memset(key, 0, session->remote.mac->key_len);
 			LIBSSH2_FREE(session, key);
 		}
 	}
@@ -596,21 +596,18 @@ static int libssh2_kex_method_diffie_hellman_group_exchange_sha1_key_exchange(LI
 
 LIBSSH2_KEX_METHOD libssh2_kex_method_diffie_helman_group1_sha1 = {
 	"diffie-hellman-group1-sha1",
-	SHA_DIGEST_LENGTH,
 	libssh2_kex_method_diffie_hellman_group1_sha1_key_exchange,
 	LIBSSH2_KEX_METHOD_FLAG_REQ_SIGN_HOSTKEY,
 };
 
 LIBSSH2_KEX_METHOD libssh2_kex_method_diffie_helman_group14_sha1 = {
 	"diffie-hellman-group14-sha1",
-	SHA_DIGEST_LENGTH,
 	libssh2_kex_method_diffie_hellman_group14_sha1_key_exchange,
 	LIBSSH2_KEX_METHOD_FLAG_REQ_SIGN_HOSTKEY,
 };
 
 LIBSSH2_KEX_METHOD libssh2_kex_method_diffie_helman_group_exchange_sha1 = {
 	"diffie-hellman-group-exchange-sha1",
-	SHA_DIGEST_LENGTH,
 	libssh2_kex_method_diffie_hellman_group_exchange_sha1_key_exchange,
 	LIBSSH2_KEX_METHOD_FLAG_REQ_SIGN_HOSTKEY,
 };
diff --git a/src/mac.c b/src/mac.c
index 6981c821..4917b904 100644
--- a/src/mac.c
+++ b/src/mac.c
@@ -54,6 +54,7 @@ static int libssh2_mac_none_MAC(LIBSSH2_SESSION *session, unsigned char *buf, un
 static LIBSSH2_MAC_METHOD libssh2_mac_method_none = {
 	"none",
 	0,
+	0,
 	NULL,
 	libssh2_mac_none_MAC,
 	NULL
@@ -98,7 +99,7 @@ static int libssh2_mac_method_hmac_sha1_hash(LIBSSH2_SESSION *session, unsigned
 
 	libssh2_htonu32(seqno_buf, seqno);
 
-	HMAC_Init(&ctx, *abstract, session->kex->key_len, EVP_sha1());
+	HMAC_Init(&ctx, *abstract, 20, EVP_sha1());
 	HMAC_Update(&ctx, seqno_buf, 4);
 	HMAC_Update(&ctx, packet, packet_len);
 	if (addtl && addtl_len) {
@@ -113,7 +114,8 @@ static int libssh2_mac_method_hmac_sha1_hash(LIBSSH2_SESSION *session, unsigned
 
 static LIBSSH2_MAC_METHOD libssh2_mac_method_hmac_sha1 = {
 	"hmac-sha1",
-	SHA_DIGEST_LENGTH,
+	20,
+	20,
 	libssh2_mac_method_common_init,
 	libssh2_mac_method_hmac_sha1_hash,
 	libssh2_mac_method_common_dtor,
@@ -137,13 +139,13 @@ static int libssh2_mac_method_hmac_sha1_96_hash(LIBSSH2_SESSION *session, unsign
 
 static LIBSSH2_MAC_METHOD libssh2_mac_method_hmac_sha1_96 = {
 	"hmac-sha1-96",
-	96 / 8,
+	12,
+	20,
 	libssh2_mac_method_common_init,
 	libssh2_mac_method_hmac_sha1_96_hash,
 	libssh2_mac_method_common_dtor,
 };
 
-#ifdef WHY_DOESNT_MD5_WORK
 /* {{{ libssh2_mac_method_hmac_md5_hash
  * Calculate hash using full md5 value
  */
@@ -156,7 +158,7 @@ static int libssh2_mac_method_hmac_md5_hash(LIBSSH2_SESSION *session, unsigned c
 
 	libssh2_htonu32(seqno_buf, seqno);
 
-	HMAC_Init(&ctx, *abstract, session->kex->key_len, EVP_md5());
+	HMAC_Init(&ctx, *abstract, 16, EVP_md5());
 	HMAC_Update(&ctx, seqno_buf, 4);
 	HMAC_Update(&ctx, packet, packet_len);
 	if (addtl && addtl_len) {
@@ -171,7 +173,8 @@ static int libssh2_mac_method_hmac_md5_hash(LIBSSH2_SESSION *session, unsigned c
 
 static LIBSSH2_MAC_METHOD libssh2_mac_method_hmac_md5 = {
 	"hmac-md5",
-	MD5_DIGEST_LENGTH,
+	16,
+	16,
 	libssh2_mac_method_common_init,
 	libssh2_mac_method_hmac_md5_hash,
 	libssh2_mac_method_common_dtor,
@@ -180,8 +183,8 @@ static LIBSSH2_MAC_METHOD libssh2_mac_method_hmac_md5 = {
 /* {{{ libssh2_mac_method_hmac_md5_96_hash
  * Calculate hash using first 96 bits of md5 value
  */
-static int libssh2_mac_method_hmac_md5_96_hash(LIBSSH2_SESSION *session, unsigned char *buf, unsigned seqno,
-																		 const unsigned char *packet, unsigned packet_len,
+static int libssh2_mac_method_hmac_md5_96_hash(LIBSSH2_SESSION *session, unsigned char *buf, unsigned long seqno,
+																		 const unsigned char *packet, unsigned long packet_len,
 																		 const unsigned char *addtl, unsigned long addtl_len, void **abstract)
 {
 	char temp[MD5_DIGEST_LENGTH];
@@ -195,12 +198,12 @@ static int libssh2_mac_method_hmac_md5_96_hash(LIBSSH2_SESSION *session, unsigne
 
 static LIBSSH2_MAC_METHOD libssh2_mac_method_hmac_md5_96 = {
 	"hmac-md5-96",
-	96 / 8,
+	12,
+	16,
 	libssh2_mac_method_common_init,
 	libssh2_mac_method_hmac_md5_96_hash,
 	libssh2_mac_method_common_dtor,
 };
-#endif /* WHY_DOESNT_MD5_WORK */
 
 #ifndef OPENSSL_NO_RIPEMD
 /* {{{ libssh2_mac_method_hmac_ripemd160_hash
@@ -215,7 +218,7 @@ static int libssh2_mac_method_hmac_ripemd160_hash(LIBSSH2_SESSION *session, unsi
 
 	libssh2_htonu32(seqno_buf, seqno);
 
-	HMAC_Init(&ctx, *abstract, session->kex->key_len, EVP_ripemd160());
+	HMAC_Init(&ctx, *abstract, 20, EVP_ripemd160());
 	HMAC_Update(&ctx, seqno_buf, 4);
 	HMAC_Update(&ctx, packet, packet_len);
 	if (addtl && addtl_len) {
@@ -230,7 +233,8 @@ static int libssh2_mac_method_hmac_ripemd160_hash(LIBSSH2_SESSION *session, unsi
 
 static LIBSSH2_MAC_METHOD libssh2_mac_method_hmac_ripemd160 = {
 	"hmac-ripemd160",
-	160 / 8,
+	20,
+	20,
 	libssh2_mac_method_common_init,
 	libssh2_mac_method_hmac_ripemd160_hash,
 	libssh2_mac_method_common_dtor,
@@ -238,7 +242,8 @@ static LIBSSH2_MAC_METHOD libssh2_mac_method_hmac_ripemd160 = {
 
 static LIBSSH2_MAC_METHOD libssh2_mac_method_hmac_ripemd160_openssh_com = {
 	"hmac-ripemd160@openssh.com",
-	160 / 8,
+	20,
+	20,
 	libssh2_mac_method_common_init,
 	libssh2_mac_method_hmac_ripemd160_hash,
 	libssh2_mac_method_common_dtor,
@@ -248,10 +253,8 @@ static LIBSSH2_MAC_METHOD libssh2_mac_method_hmac_ripemd160_openssh_com = {
 static LIBSSH2_MAC_METHOD *_libssh2_mac_methods[] = {
 	&libssh2_mac_method_hmac_sha1,
 	&libssh2_mac_method_hmac_sha1_96,
-#ifdef WHY_DOESNT_MD5_WORK
 	&libssh2_mac_method_hmac_md5,
 	&libssh2_mac_method_hmac_md5_96,
-#endif /* WHY_DOESNT_MD5_WORK */
 #ifndef OPENSSL_NO_RIPEMD
 	&libssh2_mac_method_hmac_ripemd160,
 	&libssh2_mac_method_hmac_ripemd160_openssh_com,