If you need to, just have the host DROP the table completely and then recreate it. It's just temp data, so you won't lose anything.

You'd have to do this through phpmyadmin or from the MySQL command prompt.

SQL Query
DROP table ubbt_ONLINE

Then

SQL Query
        create table ubbt_ONLINE(
        ONLINE_DISPLAY_NAME varchar(64) not null,
        USER_ID int(9) not null,
        ONLINE_LAST_ACTIVITY int(9) default '0' not null,
        ONLINE_SCRIPT_NAME varchar(64),
        ONLINE_USER_TYPE varchar(1) not null,
        ONLINE_BROWSING_FORUM varchar(100),
        ONLINE_USER_IP varchar(15),
        UNIQUE Oindx1 (ONLINE_DISPLAY_NAME),
        INDEX Oindx2 (ONLINE_LAST_ACTIVITY),
        INDEX type_index(ONLINE_USER_TYPE)
        ) TYPE=MyISAM