diff --git a/src/backend/commands/user.c b/src/backend/commands/user.c
index 3b730a3a0d80ee511c4859063daa8ef8f3619f48..d830dfdfc9049c230f1dd8c682ea83acfd1fdbfc 100644
--- a/src/backend/commands/user.c
+++ b/src/backend/commands/user.c
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Header: /cvsroot/pgsql/src/backend/commands/user.c,v 1.81 2001/08/15 21:08:20 momjian Exp $
+ * $Header: /cvsroot/pgsql/src/backend/commands/user.c,v 1.82 2001/08/17 02:59:19 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -351,7 +351,8 @@ CreateUser(CreateUserStmt *stmt)
 				DirectFunctionCall1(textin, CStringGetDatum(password));
 		else
 		{
-			if (!EncryptMD5(password, stmt->user, encrypted_password))
+			if (!EncryptMD5(password, stmt->user, strlen(stmt->user),
+				encrypted_password))
 				elog(ERROR, "CREATE USER: password encryption failed");
 			new_record[Anum_pg_shadow_passwd - 1] =
 				DirectFunctionCall1(textin, CStringGetDatum(encrypted_password));
@@ -583,7 +584,8 @@ AlterUser(AlterUserStmt *stmt)
 				DirectFunctionCall1(textin, CStringGetDatum(password));
 		else
 		{
-			if (!EncryptMD5(password, stmt->user, encrypted_password))
+			if (!EncryptMD5(password, stmt->user, strlen(stmt->user),
+				encrypted_password))
 				elog(ERROR, "CREATE USER: password encryption failed");
 			new_record[Anum_pg_shadow_passwd - 1] =
 				DirectFunctionCall1(textin, CStringGetDatum(encrypted_password));
diff --git a/src/backend/libpq/auth.c b/src/backend/libpq/auth.c
index c139f93f715cca3861b25c4684bf3a18a55a0ca0..048f67c3013626ff0ed0a70263f3171e3e380e1e 100644
--- a/src/backend/libpq/auth.c
+++ b/src/backend/libpq/auth.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/libpq/auth.c,v 1.59 2001/08/16 16:24:15 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/libpq/auth.c,v 1.60 2001/08/17 02:59:19 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -536,10 +536,17 @@ sendAuthRequest(Port *port, AuthRequest areq)
 	pq_sendint(&buf, (int32) areq, sizeof(int32));
 
 	/* Add the salt for encrypted passwords. */
-	if (areq == AUTH_REQ_CRYPT || areq == AUTH_REQ_MD5)
+	if (areq == AUTH_REQ_MD5)
 	{
-		pq_sendint(&buf, port->salt[0], 1);
-		pq_sendint(&buf, port->salt[1], 1);
+		pq_sendint(&buf, port->md5Salt[0], 1);
+		pq_sendint(&buf, port->md5Salt[1], 1);
+		pq_sendint(&buf, port->md5Salt[2], 1);
+		pq_sendint(&buf, port->md5Salt[3], 1);
+	}
+	if (areq == AUTH_REQ_CRYPT)
+	{
+		pq_sendint(&buf, port->cryptSalt[0], 1);
+		pq_sendint(&buf, port->cryptSalt[1], 1);
 	}
 
 	pq_endmessage(&buf);
diff --git a/src/backend/libpq/crypt.c b/src/backend/libpq/crypt.c
index a08c4f6baae9a2772f7ad5a89463f79d3d291de3..f82e44ccb25d8b078fa9136d6dcf78f9382425a0 100644
--- a/src/backend/libpq/crypt.c
+++ b/src/backend/libpq/crypt.c
@@ -9,7 +9,7 @@
  * Dec 17, 1997 - Todd A. Brandys
  *	Orignal Version Completed.
  *
- * $Id: crypt.c,v 1.34 2001/08/15 21:08:21 momjian Exp $
+ * $Id: crypt.c,v 1.35 2001/08/17 02:59:19 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -19,6 +19,7 @@
 
 #include "postgres.h"
 #include "libpq/crypt.h"
+#include "libpq/libpq.h"
 #include "miscadmin.h"
 #include "storage/fd.h"
 #include "utils/nabstime.h"
@@ -276,22 +277,33 @@ md5_crypt_verify(const Port *port, const char *user, const char *pgpass)
 		return STATUS_ERROR;
 	}
 
+	/* If they encrypt their password, force MD5 */
+	if (isMD5(passwd) && port->auth_method != uaMD5)
+	{
+		snprintf(PQerrormsg, PQERRORMSG_LENGTH,
+		 	"Password is stored MD5 encrypted.  "
+			"Only pg_hba.conf's MD5 protocol can be used for this user.\n");
+		fputs(PQerrormsg, stderr);
+		pqdebug("%s", PQerrormsg);
+		return STATUS_ERROR;
+	}
+
 	/*
 	 * Compare with the encrypted or plain password depending on the
 	 * authentication method being used for this connection.
 	 */
-	 switch (port->auth_method)
-	 {
+	switch (port->auth_method)
+	{
 		case uaCrypt:
-			crypt_pwd = crypt(passwd, port->salt);
+			crypt_pwd = crypt(passwd, port->cryptSalt);
 			break;
 		case uaMD5:
 			crypt_pwd = palloc(MD5_PASSWD_LEN+1);
-
 			if (isMD5(passwd))
 			{
 				if (!EncryptMD5(passwd + strlen("md5"),
-								(char *)port->salt, crypt_pwd))
+								(char *)port->md5Salt,
+								sizeof(port->md5Salt), crypt_pwd))
 				{
 					pfree(crypt_pwd);
 					return STATUS_ERROR;
@@ -301,14 +313,15 @@ md5_crypt_verify(const Port *port, const char *user, const char *pgpass)
 			{
 				char *crypt_pwd2 = palloc(MD5_PASSWD_LEN+1);
 
-				if (!EncryptMD5(passwd, port->user, crypt_pwd2))
+				if (!EncryptMD5(passwd, port->user, strlen(port->user),
+								crypt_pwd2))
 				{
 					pfree(crypt_pwd);
 					pfree(crypt_pwd2);
 					return STATUS_ERROR;
 				}
-				if (!EncryptMD5(crypt_pwd2 + strlen("md5"), port->salt,
-								crypt_pwd))
+				if (!EncryptMD5(crypt_pwd2 + strlen("md5"), port->md5Salt,
+								sizeof(port->md5Salt), crypt_pwd))
 				{
 					pfree(crypt_pwd);
 					pfree(crypt_pwd2);
@@ -324,7 +337,6 @@ md5_crypt_verify(const Port *port, const char *user, const char *pgpass)
 
 	if (!strcmp(pgpass, crypt_pwd))
 	{
-
 		/*
 		 * check here to be sure we are not past valuntil
 		 */
diff --git a/src/backend/libpq/md5.c b/src/backend/libpq/md5.c
index 846202a7b17b6f5e8aa3eaabc07e7cc20bd80de5..76d54d50b0d799e24aa60ae8c039e8e38590b7c4 100644
--- a/src/backend/libpq/md5.c
+++ b/src/backend/libpq/md5.c
@@ -295,16 +295,18 @@ md5_hash(const void *buff, size_t len, char *hexsum)
  * puts  md5(username+passwd)  in buf provided buflen is at least 36 bytes
  * returns 1 on success, 0 on any kind of failure and sets errno accordingly
  */
-bool EncryptMD5(const char *passwd, const char *salt, char *buf)
+bool EncryptMD5(const char *passwd, const char *salt, size_t salt_len,
+				char *buf)
 {
 	char crypt_buf[128];
 
-	if (strlen(salt) + strlen(passwd) > 127)
+	if (salt_len + strlen(passwd) > 127)
 		return false;
 
 	strcpy(buf, "md5");
 	memset(crypt_buf, 0, 128);
-	sprintf(crypt_buf,"%s%s", salt, passwd);
+	memcpy(crypt_buf, salt, salt_len);
+	memcpy(crypt_buf+salt_len, passwd, strlen(passwd));
 
-	return md5_hash(crypt_buf, strlen(crypt_buf), buf + 3);
+	return md5_hash(crypt_buf, salt_len + strlen(passwd), buf + 3);
 }
diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c
index c3036630bc55544a282ec150624265753f55bb2c..1a6ebec5daf287b3c5fee362ede308c5ba2cdc95 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -37,7 +37,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/postmaster/postmaster.c,v 1.235 2001/08/05 02:06:50 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/postmaster/postmaster.c,v 1.236 2001/08/17 02:59:19 momjian Exp $
  *
  * NOTES
  *
@@ -243,7 +243,7 @@ static void	processCancelRequest(Port *port, void *pkt);
 static int	initMasks(fd_set *rmask, fd_set *wmask);
 static char *canAcceptConnections(void);
 static long PostmasterRandom(void);
-static void RandomSalt(char *salt);
+static void RandomSalt(char *cryptSalt, char *md5Salt);
 static void SignalChildren(int signal);
 static int	CountChildren(void);
 static bool CreateOptsFile(int argc, char *argv[]);
@@ -1211,7 +1211,7 @@ ConnCreate(int serverFd)
 	}
 	else
 	{
-		RandomSalt(port->salt);
+		RandomSalt(port->cryptSalt, port->md5Salt);
 		port->pktInfo.state = Idle;
 	}
 
@@ -2099,12 +2099,19 @@ CharRemap(long int ch)
  * RandomSalt
  */
 static void
-RandomSalt(char *salt)
+RandomSalt(char *cryptSalt, char *md5Salt)
 {
 	long		rand = PostmasterRandom();
 
-	*salt = CharRemap(rand % 62);
-	*(salt + 1) = CharRemap(rand / 62);
+	cryptSalt[0] = CharRemap(rand % 62);
+	cryptSalt[1] = CharRemap(rand / 62);
+	/* Grab top 16-bits of two random runs so as not to send full
+	   random value over the network.  The high-order bits are more random. */
+	md5Salt[0] = rand & 0xff000000;
+	md5Salt[1] = rand & 0x00ff0000;
+	rand = PostmasterRandom();
+	md5Salt[2] = rand & 0xff000000;
+	md5Salt[3] = rand & 0x00ff0000;
 }
 
 /*
diff --git a/src/include/libpq/crypt.h b/src/include/libpq/crypt.h
index 86b9f2497c5fb1dd9cf34625af6c9e1c93ab2682..bec71ca168bb608a6ab4eb0ffaf52096a19d4511 100644
--- a/src/include/libpq/crypt.h
+++ b/src/include/libpq/crypt.h
@@ -26,7 +26,8 @@ extern int md5_crypt_verify(const Port *port, const char *user, const char *pgpa
 
 extern bool md5_hash(const void *buff, size_t len, char *hexsum);
 extern bool CheckMD5Pwd(char *passwd, char *storedpwd, char *seed);
-extern bool EncryptMD5(const char *passwd, const char *salt, char *buf);
+extern bool EncryptMD5(const char *passwd, const char *salt, 
+					   size_t salt_len, char *buf);
 
 #define MD5_PASSWD_LEN	35
 
diff --git a/src/include/libpq/libpq-be.h b/src/include/libpq/libpq-be.h
index 1d4f9d06b0b6b31017d416c7ded051eb340f1edc..56e6443cb7f9deff41791df5eba578d42b924627 100644
--- a/src/include/libpq/libpq-be.h
+++ b/src/include/libpq/libpq-be.h
@@ -8,7 +8,7 @@
  * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: libpq-be.h,v 1.21 2001/01/24 19:43:24 momjian Exp $
+ * $Id: libpq-be.h,v 1.22 2001/08/17 02:59:19 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -58,7 +58,7 @@ typedef struct ErrorMessagePacket
 
 typedef struct AuthRequestPacket
 {
-	char		data[1 + sizeof(AuthRequest) + 2];		/* 'R' + the request +
+	char		data[1 + sizeof(AuthRequest) + 4];		/* 'R' + the request +
 														 * optional salt. */
 } AuthRequestPacket;
 
@@ -119,7 +119,8 @@ typedef struct Port
 	Packet		pktInfo;		/* For the packet handlers */
 	SockAddr	laddr;			/* local addr (us) */
 	SockAddr	raddr;			/* remote addr (them) */
-	char		salt[2];		/* Password salt */
+	char		md5Salt[4];		/* Password salt */
+ 	char		cryptSalt[2];	/* Password salt */
 
 	/*
 	 * Information that needs to be held during the fe/be authentication
diff --git a/src/interfaces/libpq/fe-auth.c b/src/interfaces/libpq/fe-auth.c
index d4cb0ffc31754670e70b7809f7b07d7d661aaad1..4e4a8f6d9368bfb6eb5849a8ba8ab6d69372dd2f 100644
--- a/src/interfaces/libpq/fe-auth.c
+++ b/src/interfaces/libpq/fe-auth.c
@@ -10,7 +10,7 @@
  * exceed INITIAL_EXPBUFFER_SIZE (currently 256 bytes).
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-auth.c,v 1.50 2001/08/15 21:08:21 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-auth.c,v 1.51 2001/08/17 02:59:19 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -443,7 +443,7 @@ pg_password_sendauth(PGconn *conn, const char *password, AuthRequest areq)
 	switch (areq)
 	{
 		case AUTH_REQ_CRYPT:
-			crypt_pwd = crypt(password, conn->salt);
+			crypt_pwd = crypt(password, conn->cryptSalt);
 			break;
 		case AUTH_REQ_MD5:
 			{
@@ -455,14 +455,15 @@ pg_password_sendauth(PGconn *conn, const char *password, AuthRequest areq)
 					perror("malloc");
 					return STATUS_ERROR;
 				}
-				if (!EncryptMD5(password, conn->pguser, crypt_pwd2))
+				if (!EncryptMD5(password, conn->pguser,
+								strlen(conn->pguser), crypt_pwd2))
 				{
 					free(crypt_pwd);
 					free(crypt_pwd2);
 					return STATUS_ERROR;
 				}
-				if (!EncryptMD5(crypt_pwd2 + strlen("md5"), conn->salt,
-								crypt_pwd))
+				if (!EncryptMD5(crypt_pwd2 + strlen("md5"), conn->md5Salt,
+								sizeof(conn->md5Salt), crypt_pwd))
 				{
 					free(crypt_pwd);
 					free(crypt_pwd2);
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 32983c53ad1a57a195b3fed2dd3e2cb58e451051..d97c1004b37a34038cecf75c5a496c3127077da3 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-connect.c,v 1.173 2001/08/15 18:42:15 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-connect.c,v 1.174 2001/08/17 02:59:20 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1341,9 +1341,19 @@ keep_going:						/* We will come back to here until there
 				}
 
 				/* Get the password salt if there is one. */
-				if (areq == AUTH_REQ_CRYPT || areq == AUTH_REQ_MD5)
+				if (areq == AUTH_REQ_MD5)
 				{
-					if (pqGetnchar(conn->salt, sizeof(conn->salt), conn))
+					if (pqGetnchar(conn->md5Salt,
+								   sizeof(conn->md5Salt), conn))
+					{
+						/* We'll come back when there are more data */
+						return PGRES_POLLING_READING;
+					}
+				}
+				if (areq == AUTH_REQ_CRYPT)
+				{
+					if (pqGetnchar(conn->cryptSalt,
+								   sizeof(conn->cryptSalt), conn))
 					{
 						/* We'll come back when there are more data */
 						return PGRES_POLLING_READING;
diff --git a/src/interfaces/libpq/libpq-int.h b/src/interfaces/libpq/libpq-int.h
index bab52c390b394bb2f470d8f44556573b66974465..580ac0f0698010b7e38c7500a38bebc91bde0740 100644
--- a/src/interfaces/libpq/libpq-int.h
+++ b/src/interfaces/libpq/libpq-int.h
@@ -12,7 +12,7 @@
  * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: libpq-int.h,v 1.38 2001/08/16 04:27:18 momjian Exp $
+ * $Id: libpq-int.h,v 1.39 2001/08/17 02:59:20 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -236,7 +236,8 @@ struct pg_conn
 	/* Miscellaneous stuff */
 	int			be_pid;			/* PID of backend --- needed for cancels */
 	int			be_key;			/* key of backend --- needed for cancels */
-	char		salt[2];		/* password salt received from backend */
+ 	char		md5Salt[4];		/* password salt received from backend */
+ 	char		cryptSalt[2];		/* password salt received from backend */
 	PGlobjfuncs *lobjfuncs;		/* private state for large-object access
 								 * fns */
 
diff --git a/src/interfaces/odbc/connection.c b/src/interfaces/odbc/connection.c
index 42196df9eedd2e005edc350f51b15ba32643f388..8c9719745f3988fcc9d9dbcf457e1af6fdc23870 100644
--- a/src/interfaces/odbc/connection.c
+++ b/src/interfaces/odbc/connection.c
@@ -507,7 +507,7 @@ CC_connect(ConnectionClass *self, char do_password)
 	int			areq = -1;
 	int			beresp;
 	char		msgbuffer[ERROR_MSG_LENGTH];
-	char		salt[2];
+	char		salt[5];
 	static char *func = "CC_connect";
 
 	mylog("%s: entering...\n", func);
@@ -677,7 +677,9 @@ CC_connect(ConnectionClass *self, char do_password)
 						mylog("auth got 'R'\n");
 
 						areq = SOCK_get_int(sock, 4);
-						if (areq == AUTH_REQ_CRYPT || areq == AUTH_REQ_MD5)
+						if (areq == AUTH_REQ_MD5)
+							SOCK_get_n_char(sock, salt, 4);
+						if (areq == AUTH_REQ_CRYPT)
 							SOCK_get_n_char(sock, salt, 2);
 
 						mylog("areq = %d\n", areq);