Error when creating a new organisation

Install for the svn, on drupal.

Everything works fine, but when creating a new organisation, it seems to have an error on the log (despite the error message, the contact is created).

unrecoverable error
Sorry. A non-recoverable error has occurred.

Database Error Code: Cannot add or update a child row: a foreign key constraint fails (`civicrm2/civicrm_log`, CONSTRAINT `FK_civicrm_log_modified_id` FOREIGN KEY (`modified_id`) REFERENCES `civicrm_contact` (`id`) ON DELETE CASCADE), 1452

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Error Details:

Array
(
[callback] => Array
(
[0] => CRM_Core_Error
[1] => handle
)

[code] => -1
[message] => DB Error: unknown error
[mode] => 16
[debug_info] => INSERT INTO civicrm_log (entity_table , entity_id , data , modified_id , modified_date ) VALUES ('civicrm_contact' , 3 , 'civicrm_contact,3' , 102 , 20080219015013 ) [nativecode=1452 ** Cannot add or update a child row: a foreign key constraint fails (`civicrm2/civicrm_log`, CONSTRAINT `FK_civicrm_log_modified_id` FOREIGN KEY (`modified_id`) REFERENCES `civicrm_contact` (`id`) ON DELETE CASCADE)]
[type] => DB_Error
[user_info] => INSERT INTO civicrm_log (entity_table , entity_id , data , modified_id , modified_date ) VALUES ('civicrm_contact' , 3 , 'civicrm_contact,3' , 102 , 20080219015013 ) [nativecode=1452 ** Cannot add or update a child row: a foreign key constraint fails (`civicrm2/civicrm_log`, CONSTRAINT `FK_civicrm_log_modified_id` FOREIGN KEY (`modified_id`) REFERENCES `civicrm_contact` (`id`) ON DELETE CASCADE)]
[to_string] => [db_error: message="DB Error: unknown error" code=-1 mode=callback callback=CRM_Core_Error::handle prefix="" info="INSERT INTO civicrm_log (entity_table , entity_id , data , modified_id , modified_date ) VALUES ('civicrm_contact' , 3 , 'civicrm_contact,3' , 102 , 20080219015013 ) [nativecode=1452 ** Cannot add or update a child row: a foreign key constraint fails (`civicrm2/civicrm_log`, CONSTRAINT `FK_civicrm_log_modified_id` FOREIGN KEY (`modified_id`) REFERENCES `civicrm_contact` (`id`) ON DELETE CASCADE)]"]
)