app_status field in Applications table does not have a default value

The poller.php script is unable to add applications from the unix-agent. The problem is the app_status field in the Applications table is marked as NOT NULL and does not define a default value. The insert statement from the unix-agent.inc.php does not include the app_status field.

Debug output from poller.php:
SQL[SELECT COUNT(*) FROM `applications` WHERE `device_id` = '12' AND `app_type` = 'apache']
Found new application 'Apache'

SQL[INSERT INTO `applications` (`device_id`,`app_type`) VALUES ('12','apache')]

SQL[SELECT COUNT(*) FROM `applications` WHERE `device_id` = '12' AND `app_type` = 'mysql']
Found new application 'MySQL'

SQL[INSERT INTO `applications` (`device_id`,`app_type`) VALUES ('12','mysql')]

Output from MySQL:
mysql> INSERT INTO `applications` (`device_id`,`app_type`) VALUES ('12','apache');
ERROR 1364 (HY000): Field 'app_status' doesn't have a default value

Possible fix:
I was unable to find the app_status field used anywhere within the system and so set a default value as follows:
ALTER TABLE applications MODIFY COLUMN app_status VARCHAR(8) NOT NULL DEFAULT '{}';