PIVOT With Dynamic Columns Names Created

I am trying to do a PIVOT on a query result, but the column names created by the PIVOT function are dynamic.

For example (modified from the SQL Server 2005 Books Online documentation on the PIVOT operator) :

SELECT
Division,
[2] AS CurrentPeriod,
[1] AS PreviousPeriod
FROM
(
SELECT
Period,
Division,
Sales_Amount
FROM
Sales.SalesOrderHeader
WHERE
(
Period = @period
OR Period = @period - 1
)
) p
PIVOT
(
SUM (Sales_Amount)
FOR Period IN ( [2], [1] )
) AS pvt

Let's assume that any value 2 is selected for the @period parameter, and returns the sales by division for periods 2 and 1 (2 minus 1).

Division CurrentPeriod PreviousPeriodA 400 3000 B 400 100 C 470 300 D 800 2500 E 1000 1900

What if the value @period were to be changed, to say period 4 and it should returns the sales for periods 4 and 3 for example, is there a way I can change to code above to still perform the PIVOT while dynamically accepting the period values 4 and 3, applying it to the columns names in the first SELECT statement and the FOR ... IN clause in the PIVOT statement ?

Need a way to represent the following [2] and [1] column names dynamically depending on the value in the @period parameter.

[2] AS CurrentPeriod,
[1] AS PreviousPeriod

FOR Period IN ( [2], [1] )

I have tried to use the @period but it doesn't work.

Thanks in advance.

Kenny