[Marco van Herwaarden]

You can run the following 2 queries:
[sql]ALTER TABLE usergroup CHANGE COLUMN mh_unm_changelimit mh_unm_changelimit SMALLINT UNSIGNED DEFAULT 30 NOT NULL;
ALTER TABLE usergroup CHANGE COLUMN mh_unm_viewhistorylimit mh_unm_viewhistorylimit SMALLINT UNSIGNED DEFAULT 1 NOT NULL;[/sql]
If you are using a table prefix, then add it in front of the tablename (ie. prefix_usergroup).

If you run the queries from the AdminCP, you must run 1 line at a time. If you are using something like phpMyAdmin, you can just copy&paste both lines in 1 go.