Similar to, but not exactly the same as http://bugs.mysql.com/bug.php?id=65116.

Only shows up on cluster, standalone install work fine.

Create the following table:
CREATE TABLE `auto_inc` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`data` varchar(45) DEFAULT NULL,
PRIMARY KEY (`id`),
UNIQUE KEY `data_UNIQUE` (`data`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

Insert some data using REPLACE INTO:

REPLACE INTO auto_inc (data) VALUES ('Hello');

SHOW TABLE STATUS LIKE 'auto_inc' shows Auto_increment set to 2.

Issue the same query again:
REPLACE INTO auto_inc (data) VALUES ('Hello');

The row is now updated with id=2, but auto_increment is unchanged. On next insert this will result in duplicate key error.