Big parameter list for SQL query

I have a big list of int parameters for a SQL query:

update mytable set col='xyz'
where id in (/* thousands of ints */)

My problem is that in SQL Server 2000 there are a limit for parameters. I could run this query on an SQL Server 2008 too.

What is the better way to do this.

Edit:

The list of Ids come from a C# program. Not from another table.