jazmo_ on "[Plugin: Weekly Class Schedule] Mysql errors"

When i try to install this plugin, it gives following errors:

WordPress database error: [Specified key was too long; max key length is 767 bytes]
CREATE TABLE wp_wcs2_class ( id int(11) NOT NULL AUTO_INCREMENT, class_name varchar(256) DEFAULT '' NOT NULL, class_description text, time_created varchar(50) NOT NULL DEFAULT '', user_created bigint(20) NOT NULL, time_modified varchar(50) NOT NULL DEFAULT '', user_modified bigint(20) NOT NULL, PRIMARY KEY (id), UNIQUE KEY class_name (class_name) )

WordPress database error: [Specified key was too long; max key length is 767 bytes]
CREATE TABLE wp_wcs2_classroom ( id int(11) NOT NULL AUTO_INCREMENT, classroom_name varchar(256) NOT NULL DEFAULT '', classroom_description text, time_created varchar(50) NOT NULL DEFAULT '', user_created bigint(20) NOT NULL, time_modified varchar(50) NOT NULL DEFAULT '', user_modified bigint(20) NOT NULL, PRIMARY KEY (id), UNIQUE KEY classroom_name (classroom_name) )

WordPress database error: [Specified key was too long; max key length is 767 bytes]
CREATE TABLE wp_wcs2_instructor ( id int(11) NOT NULL AUTO_INCREMENT, instructor_name varchar(256) NOT NULL DEFAULT '', instructor_description text, time_created varchar(50) NOT NULL DEFAULT '', user_created bigint(20) NOT NULL, time_modified varchar(50) NOT NULL DEFAULT '', user_modified bigint(20) NOT NULL, PRIMARY KEY (id), UNIQUE KEY instructor_name (instructor_name) )

I don't quite get the problem.

http://wordpress.org/plugins/weekly-class-schedule/