diff --git a/source/passdb/ldap.c b/source/passdb/ldap.c
index 54566e454b9..b520f521bdd 100644
--- a/source/passdb/ldap.c
+++ b/source/passdb/ldap.c
@@ -356,8 +356,8 @@ static void ldap_get_sam_passwd(LDAP *ldap_struct, LDAPMessage *entry,
 	user->logon_divs = 168; /* hours per week */
 	user->hours_len = 21; /* 21 times 8 bits = 168 */
 	memset(user->hours, 0xff, user->hours_len); /* available at all hours */
-	user->unknown_5 = 0x00020000; /* don't know */
-	user->unknown_5 = 0x000004ec; /* don't know */
+	user->unknown_5 = 0x00000000; /* don't know */
+	user->unknown_6 = 0x000004ec; /* don't know */
 
 	if (user->acct_ctrl & (ACB_DOMTRUST|ACB_WSTRUST|ACB_SVRTRUST) )
 	{
diff --git a/source/passdb/nispass.c b/source/passdb/nispass.c
index 4b4e281c29d..2959f6ca7c5 100644
--- a/source/passdb/nispass.c
+++ b/source/passdb/nispass.c
@@ -353,7 +353,7 @@ static BOOL make_sam_from_nisp_object(struct sam_passwd *pw_buf, nis_object *obj
 	pw_buf->logon_divs = 168; /* hours per week */
 	pw_buf->hours_len = 21; /* 21 times 8 bits = 168 */
 	memset(pw_buf->hours, 0xff, pw_buf->hours_len); /* available at all hours */
-	pw_buf->unknown_5 = 0x00020000; /* don't know */
+	pw_buf->unknown_5 = 0x00000000; /* don't know */
 	pw_buf->unknown_6 = 0x000004ec; /* don't know */
 
 	return True;
diff --git a/source/passdb/passdb.c b/source/passdb/passdb.c
index 0e4948a3226..428dd004eee 100644
--- a/source/passdb/passdb.c
+++ b/source/passdb/passdb.c
@@ -116,9 +116,8 @@ void pdb_init_sam(SAM_ACCOUNT *user)
 	user->logon_divs = 168; 	/* hours per week */
 	user->hours_len = 21; 		/* 21 times 8 bits = 168 */
 	memset(user->hours, 0xff, user->hours_len); /* available at all hours */
-	user->unknown_5 = 0x00020000; 	/* don't know */
-	user->unknown_5 = 0x000004ec; 	/* don't know */
-	
+	user->unknown_5 = 0x00000000; /* don't know */
+	user->unknown_6 = 0x000004ec; /* don't know */
 }
 
 /************************************************************
diff --git a/source/rpc_parse/parse_prs.c b/source/rpc_parse/parse_prs.c
index 56d03daf18f..1ec3f72d4c9 100644
--- a/source/rpc_parse/parse_prs.c
+++ b/source/rpc_parse/parse_prs.c
@@ -673,16 +673,16 @@ BOOL prs_unistr2(BOOL charmode, char *name, prs_struct *ps, int depth, UNISTR2 *
 	if (q == NULL)
 		return False;
 
+	/* If the string is empty, we don't have anything to stream */
+	if (str->uni_str_len==0)
+		return True;
+
 	if (UNMARSHALLING(ps)) {
 		str->buffer = (uint16 *)prs_alloc_mem(ps,str->uni_max_len * sizeof(uint16));
 		if (str->buffer == NULL)
 			return False;
 	}
 
-	/* If the string is empty, we don't have anything to stream */
-	if (str->uni_str_len==0)
-		return True;
-
 	p = (char *)str->buffer;
 
 	/* If we're using big-endian, reverse to get little-endian. */