Comments error “comment_agent’ column

If someone wants to send a comment, the following error-message comes.
(I’ve the last nightly build. If installed wp-stattraq and subscribe-to-comments, but to deactivate plug-ins has no effect; things with whitespace I’ve checked.)
Database error: [Unknown column ‘comment_agent’ in ‘field list’]
INSERT INTO wp1_comments (comment_post_ID, comment_author, comment_author_email, comment_author_url, comment_author_IP, comment_date, comment_date_gmt, comment_content, comment_approved, comment_agent) VALUES (’49’, ‘ich’, ”, ”, ‘217.82.71.46’, ‘2004-09-09 17:37:58’, ‘2004-09-09 15:37:58’, ‘test’, ‘1’, ‘Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; MyIE2; Maxthon; .NET CLR 1.1.4322; FDM)’)
Warning: Cannot modify header information – headers already sent by (output started at /usr/www/users/herbert/blog/wp-includes/wp-db.php:98) in /usr/www/users/herbert/blog/wp-comments-post.php on line 92
Warning: Cannot modify header information – headers already sent by (output started at /usr/www/users/herbert/blog/wp-includes/wp-db.php:98) in /usr/www/users/herbert/blog/wp-comments-post.php on line 93
Warning: Cannot modify header information – headers already sent by (output started at /usr/www/users/herbert/blog/wp-includes/wp-db.php:98) in /usr/www/users/herbert/blog/wp-comments-post.php on line 94
Warning: Cannot modify header information – headers already sent by (output started at /usr/www/users/herbert/blog/wp-includes/wp-db.php:98) in /usr/www/users/herbert/blog/wp-comments-post.php on line 96
Warning: Cannot modify header information – headers already sent by (output started at /usr/www/users/herbert/blog/wp-includes/wp-db.php:98) in /usr/www/users/herbert/blog/wp-comments-post.php on line 97
Warning: Cannot modify header information – headers already sent by (output started at /usr/www/users/herbert/blog/wp-includes/wp-db.php:98) in /usr/www/users/herbert/blog/wp-comments-post.php on line 98
Warning: Cannot modify header information – headers already sent by (output started at /usr/www/users/herbert/blog/wp-includes/wp-db.php:98) in /usr/www/users/herbert/blog/wp-comments-post.php on line 99
Warning: Cannot modify header information – headers already sent by (output started at /usr/www/users/herbert/blog/wp-includes/wp-db.php:98) in /usr/www/users/herbert/blog/wp-comments-post.php on line 104