phpBB : Critical Error

Error creating new session

DEBUG MODE

SQL Error : 1062 Duplicate entry '-1' for key 2

INSERT INTO phpbb_sessions (session_id, session_user_id, session_start, session_time, session_ip, session_page, session_logged_in, session_admin) VALUES ('49252464571934cd8059d6ab3ec8ee9d', -1, 1329955251, 1329955251, '266bb3d9', 0, 0, 0)

Line : 187
File : sessions.php