Found it and here is what you can do....
//the postback from the first uploader
protected void Uploader_FileUploaded(object sender, UploaderEventArgs args)
{
if (sender == this.upPrimary)
{
string filename = args.FileName.Substring(0, args.FileName.Length - 4);
upAssoicates.DialogFilter =
string.Format("Assoicated Point Files|{0}.CB*;{0}.EC*;{0}.FDH;{0}.FM*;{0}.S0*;{0}.LP2", filename);
upAssoicates.InsertButton.Enabled =
true;
}
}
Bo