Date Problem with Time.

Hi all,
I have one stored procedure which have startdate and enddate as parameter. If I execute the Stored Procedure with the startdate and enddate, it is taking time as 00:00:000 as default. But I want to take the default time as 00:00 for startdate and 23:59 for end date. Can anybody guide how to make this...advance thanks.

What I want is ...if I give the date without giving time for the paratmeters, then startdate should take the time 00:00 and enddate should take the time as 23:59

declare @startDatedatetime,
@endDatedatetime

select @startdate = getdate()
select @startdate = dateadd(dd, 0, datediff(dd, 0, @startdate))

select @endDate = dateadd(ms, -2, dateadd(dd, 1, @startdate))
select @startdate, @endDate
Bambola.