I get errno: 150 eventhough SET FOREIGN_KEY_CHECKS=0;

[lagu2653]

I have a table with a lot of foreign keys. I want to change tinyint(3) to int(10).

I have:
| publishers | CREATE TABLE `publishers` (
`publisher_id` tinyint(5) unsigned NOT NULL AUTO_INCREMENT,
`market_id` tinyint(3) unsigned NOT NULL,
`name` varchar(50) NOT NULL,
`code` char(10) NOT NULL,
`timezone` varchar(50) NOT NULL DEFAULT 'Europe/Stockholm',
`status` enum('paused','active') NOT NULL DEFAULT 'active',
`created` timestamp NOT NULL DEFAULT '1971-01-01 00:00:00',
`updated` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
PRIMARY KEY (`publisher_id`),
UNIQUE KEY `UNIQUE_MARKET_ID_NAME_CODE` (`market_id`,`name`,`code`),
CONSTRAINT `publishers_ibfk_1` FOREIGN KEY (`market_id`) REFERENCES `markets` (`market_id`) ON DELETE CASCADE ON UPDATE
CASCADE
) ENGINE=InnoDB AUTO_INCREMENT=188 DEFAULT CHARSET=utf8 |

which I want to change to

| publishers | CREATE TABLE `publishers` (
`publisher_id` int(10) unsigned NOT NULL AUTO_INCREMENT,
`market_id` tinyint(3) unsigned NOT NULL,
`name` varchar(50) NOT NULL,
`code` char(10) NOT NULL,
`timezone` varchar(50) NOT NULL DEFAULT 'Europe/Stockholm',
`status` enum('paused','active') NOT NULL DEFAULT 'active',
`created` timestamp NOT NULL DEFAULT '1971-01-01 00:00:00',
`updated` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
PRIMARY KEY (`publisher_id`),
UNIQUE KEY `UNIQUE_MARKET_ID_NAME_CODE` (`market_id`,`name`,`code`),
CONSTRAINT `publishers_ibfk_1` FOREIGN KEY (`market_id`) REFERENCES `markets` (`market_id`) ON DELETE CASCADE ON UPDATE
CASCADE
) ENGINE=InnoDB AUTO_INCREMENT=188 DEFAULT CHARSET=utf8 |

when I run:
SET FOREIGN_KEY_CHECKS=0;
alter table `publishers` modify column `publisher_id` int(10) unsigned NOT NULL AUTO_INCREMENT;
SET FOREIGN_KEY_CHECKS=1;

I get:
ERROR 1025 (HY000): Error on rename of './adxsearch_2011_10_21/#sql-60de_3670d4' to './adxsearch_2011_10_21/publishers' (errno: 150)

How do I rectify this problem so I can change the column to int(10)?

[lagu2653]

Sorry, was supposed to be tinyint(5)!

[lagu2653]

I solved it by
1. Dropping the Foreign Key constraints for all tables affected.
2. Altering my tables.
3. Re-inserting my foreign key constraints.