CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP

MySQL retourneerde: 


You have an error in your SQL syntax.  Check the manual that corresponds to your MySQL server version for the right syntax to use near 'CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP,
  PRIMARY KEY  

MySQL retourneerde: 
 
 
You have an error in your SQL syntax.  Check the manual that corresponds to your MySQL server version for the right syntax to use near 'CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP,
  PRIMARY KEY

CREATE TABLE `[koopuit_logs]` (
  `buy_id` mediumint(6) unsigned NOT NULL auto_increment,
  `login` varchar(30)   NOT NULL default '',
  `wie` varchar(30)   NOT NULL default '',
  `voor` smallint(4) NOT NULL default '0',
  `wanneer` timestamp NOT NULL default CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP,
  PRIMARY KEY  (`buy_id`)
);

CREATE TABLE `[koopuit_logs]` (
  `buy_id` mediumint(6) unsigned NOT NULL auto_increment,
  `login` varchar(30)   NOT NULL default '',
  `wie` varchar(30)   NOT NULL default '',
  `voor` smallint(4) NOT NULL default '0',
  `wanneer` timestamp NOT NULL default CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP,
  PRIMARY KEY  (`buy_id`)
);