date problem

hi.........
its not a big problem, but i'm sliping something.
i have smalldatetime field that store date & time. but when i compare date with only date format, query doen't show any result.
example:

in table the date field store is: 11/28/2007 00:25:00
now, i ' m using
select * from emp where cDate =CONVERT(VARCHAR(10),'11/28/2007',111)
it doesn't return any answer.

but if i use
 select * from emp where cDate >=CONVERT(VARCHAR(10),'11/28/2007',111)
it will show the result.
please help us.

thanks