erreur sql sur une recherche

Voici le message :

" SELECT articles.* FROM `yacs_articles` AS articles, `yacs_sections` AS sections WHERE ((articles.anchor_type LIKE 'section') AND (articles.anchor_id = sections.id)) AND ((articles.active='Y' OR articles.active='R' OR articles.active='N') AND ((articles.expiry_date is NULL) OR (articles.expiry_date = '0000-00-00 00:00:00') OR (articles.expiry_date > '2007-09-12 08:44:48')))MATCH(articles.title, articles.source, articles.introduction, articles.overlay, articles.description) AGAINST('7.9alpha10') ORDER BY articles.edit_date DESC LIMIT 0,31
1064: 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 'MATCH(articles.title, articles.source, articles.introduction, articles.overlay, ' at line 1 "