Forms Data Controls :: Gridview To Csv File Not Working For Date?

I am trying to export my GridView info to a readable csv file. Unfortunately, attached is what is shown. Under the Date column, a few dates show up (8/9/2010) but when it switches to 8/10/2010 -8/31/2010 it only shows ######, BUT when I move the mouse over the #######'s it shows the date in the little box thing.

I have this code:

protected void btnExtractCSV_Click(object sender, EventArgs e)
{
Response.Clear();
Response.Buffer = true;
Response.AddHeader("content-disposition", "attachment;filename=GridViewExport.csv");
Response.Charset = "";
Response.ContentType = "application/text";......