diff --git a/mysql-test/r/auto_increment.result b/mysql-test/r/auto_increment.result
index e79e6aab56b..2facb504294 100644
--- a/mysql-test/r/auto_increment.result
+++ b/mysql-test/r/auto_increment.result
@@ -105,3 +105,41 @@ Table	Op	Msg_type	Msg_text
 test.t1	check	warning	Found row where the auto_increment column has the value 0
 test.t1	check	status	OK
 drop table t1;
+create table t1 (i tinyint unsigned not null auto_increment primary key);
+insert into t1 set i = 254;
+insert into t1 set i = null;
+select last_insert_id();
+last_insert_id()
+255
+insert into t1 set i = null;
+Duplicate entry '255' for key 1
+select last_insert_id();
+last_insert_id()
+255
+drop table t1;
+create table t1 (i tinyint unsigned not null auto_increment, key (i));
+insert into t1 set i = 254;
+insert into t1 set i = null;
+select last_insert_id();
+last_insert_id()
+255
+insert into t1 set i = null;
+select last_insert_id();
+last_insert_id()
+255
+drop table t1;
+create table t1 (i tinyint unsigned not null auto_increment primary key, b int, unique (b));
+insert into t1 values (NULL, 10);
+select last_insert_id();
+last_insert_id()
+1
+insert into t1 values (NULL, 15);
+select last_insert_id();
+last_insert_id()
+2
+insert into t1 values (NULL, 10);
+Duplicate entry '10' for key 2
+select last_insert_id();
+last_insert_id()
+3
+drop table t1;
diff --git a/mysql-test/t/auto_increment.test b/mysql-test/t/auto_increment.test
index d7f67fe80d4..63fdfded6d0 100644
--- a/mysql-test/t/auto_increment.test
+++ b/mysql-test/t/auto_increment.test
@@ -72,3 +72,33 @@ select * from t1;
 check table t1;
 drop table t1;
 
+#
+# last_insert_id() madness
+#
+create table t1 (i tinyint unsigned not null auto_increment primary key);
+insert into t1 set i = 254;
+insert into t1 set i = null;
+select last_insert_id();
+--error 1062
+insert into t1 set i = null;
+select last_insert_id();
+drop table t1;
+
+create table t1 (i tinyint unsigned not null auto_increment, key (i));
+insert into t1 set i = 254;
+insert into t1 set i = null;
+select last_insert_id();
+insert into t1 set i = null;
+select last_insert_id();
+drop table t1;
+
+create table t1 (i tinyint unsigned not null auto_increment primary key, b int, unique (b));
+insert into t1 values (NULL, 10);
+select last_insert_id();
+insert into t1 values (NULL, 15);
+select last_insert_id();
+--error 1062
+insert into t1 values (NULL, 10);
+select last_insert_id();
+drop table t1;
+
diff --git a/sql/handler.cc b/sql/handler.cc
index 5353e78cd11..e288d590e88 100644
--- a/sql/handler.cc
+++ b/sql/handler.cc
@@ -660,8 +660,8 @@ void handler::update_auto_increment()
     thd->next_insert_id=0;			// Clear after use
   else
     nr=get_auto_increment();
-  thd->insert_id((ulonglong) nr);
-  table->next_number_field->store(nr);
+  if (!table->next_number_field->store(nr))
+    thd->insert_id((ulonglong) nr);
   auto_increment_column_changed=1;
   DBUG_VOID_RETURN;
 }