More Time Issues. Default won't go Null

I'm wondering why the following parameters, which are entered using
time_select;

Parameters: {"performer_calc_sheet_timelog"=>{"meal_end(1i)"=>"2000",
"date(1i)"=>"2006", "arrive_at_home(1i)"=>"2000",
"arrive_at_home(2i)"=>"1", "meal_end(2i)"=>"1",
"finish_time(1i)"=>"2000", "date(2i)"=>"10", "arrive_at_home(3i)"=>"1",
"finish_time(2i)"=>"1", "meal_end(3i)"=>"1", "date(3i)"=>"17",
"finish_time(3i)"=>"1", "meal_end(4i)"=>"", "meal_start(1i)"=>"2000",
"arrive_at_home(4i)"=>"", "call_time(1i)"=>"2000",
"arrive_at_home(5i)"=>"", "meal_start(2i)"=>"1", "meal_end(5i)"=>"",
"leave_home(1i)"=>"2000", "finish_time(4i)"=>"",
"arrive_at_location(1i)"=>"2000", "finish_time(5i)"=>"",
"call_time(2i)"=>"1", "leave_location(1i)"=>"2000",
"meal_start(3i)"=>"1", "leave_home(2i)"=>"1",
"arrive_at_location(2i)"=>"1", "call_time(3i)"=>"1",
"leave_location(2i)"=>"1", "meal_start(4i)"=>"", "leave_home(3i)"=>"1",
"meal_start(5i)"=>"", "leave_home(4i)"=>"02",
"leave_location(3i)"=>"1", "call_time(4i)"=>"",
"arrive_at_location(3i)"=>"1", "leave_home(5i)"=>"19",
"call_time(5i)"=>"", "leave_location(4i)"=>"",
"arrive_at_location(4i)"=>"00", "leave_location(5i)"=>"",
"arrive_at_location(5i)"=>"00"}, "commit"=>"ADD",
"action"=>"insert_performer_calc_sheet_timelog", "id"=>"42",
"controller"=>"calc_sheet"}

Generates the following SQL statement when I do
"PerformerCalcSheetTimelog.create(params[:performer_calc_sheet_timelog])

INSERT INTO performer_calc_sheet_timelogs (`leave_home`,
`leave_location`, `arrive_at_home`, `date`,
`calc_sheet_performer_line_id`, `arrive_at_location`, `call_time`,
`finish_time`, `meal_end`, `position`, `meal_start`) VALUES('2000-01-01
02:19:00', '2000-01-01 00:00:00', '2000-01-01 00:00:00', '2006-10-17',
42, '2000-01-01 00:00:00', '2000-01-01 00:00:00', '2000-01-01
00:00:00', '2000-01-01 00:00:00', 3, '2000-01-01 00:00:00')

I have the database set to receive NULL as an entry for all the times,
and if I input data using Navicat for example, they go in as NULL. The
problem is the fields in mySQL are TIME fields, so when I retrieve the
data, it can't tell if it's supposed to be Midnight ( 00:00:00 ) or
nothing.

Any help would be MUCH appreciated, I'm going bananas. Thanks