The following query:
SELECT * FROM `objects` WHERE (date_field BETWEEN \'2010-09-29 10:15:55\' AND \'2010-01-30 14:15:55\')
returns nothin
Your query should have date as
select * from table between `lowerdate` and `upperdate`
try
SELECT * FROM `objects` WHERE (date_field BETWEEN '2010-01-30 14:15:55' AND '2010-09-29 10:15:55')