diff --git a/mysql-test/r/merge.result b/mysql-test/r/merge.result
index ff4828144a7..a1ef7597143 100644
--- a/mysql-test/r/merge.result
+++ b/mysql-test/r/merge.result
@@ -178,9 +178,9 @@ t3	CREATE TABLE `t3` (
 ) ENGINE=MRG_MyISAM DEFAULT CHARSET=latin1 UNION=(`t1`,`t2`)
 create table t4 (a int not null, b char(10), key(a)) engine=MERGE UNION=(t1,t2);
 select * from t4;
-ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exists
+ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
 alter table t4 add column c int;
-ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exists
+ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
 create database mysqltest;
 create table mysqltest.t6 (a int not null primary key auto_increment, message char(20));
 create table t5 (a int not null, b char(20), key(a)) engine=MERGE UNION=(test.t1,mysqltest.t6);
@@ -775,9 +775,9 @@ DROP TABLE t1, t2;
 CREATE TABLE t1(a INT) ENGINE=MEMORY;
 CREATE TABLE t2(a INT) ENGINE=MERGE UNION=(t1);
 SELECT * FROM t2;
-ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exists
+ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
 DROP TABLE t1, t2;
 CREATE TABLE t2(a INT) ENGINE=MERGE UNION=(t3);
 SELECT * FROM t2;
-ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exists
+ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
 DROP TABLE t2;
diff --git a/sql/ha_myisammrg.cc b/sql/ha_myisammrg.cc
index edb3521470f..3408f7090f2 100644
--- a/sql/ha_myisammrg.cc
+++ b/sql/ha_myisammrg.cc
@@ -249,9 +249,22 @@ void ha_myisammrg::info(uint flag)
   if (flag & HA_STATUS_CONST)
   {
     if (table->key_parts && info.rec_per_key)
+    {
+#ifdef HAVE_purify
+      /*
+        valgrind may be unhappy about it, because optimizer may access values
+        between file->keys and table->key_parts, that will be uninitialized.
+        It's safe though, because even if opimizer will decide to use a key
+        with such a number, it'll be an error later anyway.
+      */
+      bzero((char*) table->key_info[0].rec_per_key,
+            sizeof(table->key_info[0].rec_per_key) * table->key_parts);
+#endif
       memcpy((char*) table->key_info[0].rec_per_key,
 	     (char*) info.rec_per_key,
-	     sizeof(table->key_info[0].rec_per_key)*table->key_parts);
+             sizeof(table->key_info[0].rec_per_key) *
+             min(file->keys, table->key_parts));
+    }
   }
 }
 
diff --git a/sql/share/english/errmsg.txt b/sql/share/english/errmsg.txt
index a8b06a07218..62c8f4f9991 100644
--- a/sql/share/english/errmsg.txt
+++ b/sql/share/english/errmsg.txt
@@ -184,7 +184,7 @@ character-set=latin1
 "INSERT DELAYED can't be used with table '%-.64s' because it is locked with LOCK TABLES",
 "Incorrect column name '%-.100s'",
 "The used storage engine can't index column '%-.64s'",
-"Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exists",
+"Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist",
 "Can't write, because of unique constraint, to table '%-.64s'",
 "BLOB/TEXT column '%-.64s' used in key specification without a key length",
 "All parts of a PRIMARY KEY must be NOT NULL; if you need NULL in a key, use UNIQUE instead",
diff --git a/sql/sql_update.cc b/sql/sql_update.cc
index af4ba8025f9..6742fbad5c4 100644
--- a/sql/sql_update.cc
+++ b/sql/sql_update.cc
@@ -901,6 +901,8 @@ multi_update::initialize_tables(JOIN *join)
     List<Item> temp_fields= *fields_for_table[cnt];
     ORDER     group;
 
+    if (ignore)
+      table->file->extra(HA_EXTRA_IGNORE_DUP_KEY);
     if (table == main_table)			// First table in join
     {
       if (safe_update_on_fly(join->join_tab, &temp_fields))
@@ -1007,7 +1009,11 @@ multi_update::~multi_update()
 {
   TABLE_LIST *table;
   for (table= update_tables ; table; table= table->next)
+  {
     table->table->no_keyread= table->table->no_cache= 0;
+    if (ignore)
+      table->table->file->extra(HA_EXTRA_NO_IGNORE_DUP_KEY);
+  }
 
   if (tmp_tables)
   {