Advanced search: Between dates

What is does is it fills the time portion of the date with zeroes making the search to ignore what happens in the whole day.
EVEN THOUGH I HAVE SELECTED THAT THE TIME IS A DATE FIELD in the visual editor.
If I am comparing dates date ranges and you are going to fill the time portion then why dont do the next
From: 2007-09-01 00:00:00

To: 2007-09-30 23:59:59
So it will consider the whole 30th day?
Currently it is doing the next wich does not look good to me
where (

1=1 and

upper([dbo].[BV_PSR_CONVERSION].[Created])>=upper(N'2007-9-1 0:0:0') and

upper([dbo].[BV_PSR_CONVERSION].[Created])<=upper(N'2007-9-30 0:0:0'))