Select a collation from the list in the topic you referenced that contains
the Pref clause and apply that collation to the table column. A collation
can be applied to the column definition or it can be specified in a query.
Here are a couple of examples:

CREATE TABLE Test1
(C1 int, C2 nvarchar(30)COLLATE SQL_Latin1_General_Pref_CP1_CI_AS)
GO

SELECT C1, C2
FROM Test1
ORDER BY C2 COLLATE SQL_Latin1_General_Pref_CP1_CI_AS

Here's a definition of the uppercace preference value from the book 'Inside
SQL Server 2000'. "Uppercase preference can be specified only with a
case-insensitive sort order, and it means that although 'A' and 'a' are
treated as equivalent for comparisons, 'A' is sorted before 'a'. "

Is that really what you want to do? Your original question was " How can i
configure a column collation to only accept uppercase ? "    My
interpretation of your question is that you want to limit the data in the
column to only uppercase characters.  If that is true, then changing the
collation to one that has an uppercase preference is not going to work and
using the UPPER function is the right answer.  If that's not what you want
to do, perhaps you can clarify what you are trying to do.