You can crash the program with the following query:
SELECT
users.username,
bug_history.date_modified,
bug_history.field_name,
bug_history.old_value,
bug_history.new_value,
bug_history.bug_id,
bug.summary
FROM
mantis.mantis_user_table users,
mantis.mantis_bug_history_table bug_history,
(
select bug_history2.id, bug_history2.old_val
from mantis.mantis_bug_history_table bug_history2
where bug_history2.type='2' and
bug_history2.date_modified = '2005-06-30'
)
bug_history3,
mantis.mantis_bug_table bug
WHERE
bug_history.id = bug_history3.id AND
users.id = bug_history.user_id AND
bug_history.bug_id = bug.id
ORDER BY
bug_history.date_modified