Database error (mySQL 4)

Trying the latest version (oct. 17) I get the following error. using mysql 4.1.20
user warning: 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 'fields varchar(128) NOT NULL default '', PRIMARY KEY (rid), UNIQ' at line 5 query: CREATE TABLE testcopy_rule ( rid int unsigned NOT NULL auto_increment, to_type varchar(25) NOT NULL default '', src_arg int unsigned NOT NULL default '0', fields varchar(128) NOT NULL default '', PRIMARY KEY (rid), UNIQUE KEY to_type (to_type) ) /*!40100 DEFAULT CHARACTER SET UTF8 */ in .../database.mysql.inc on line 172.

any help would be greatly appreciated