Hi, my code attempts to grab data from the RSS feed of a website. It grabs the nodes fine, but when attempting to grab the data from a node with a colon, it crashes and gives the error "Namespace Manager or XsltContext needed. This query has a prefix, variable, or user-defined function." The code is shown below:

        WebRequest request = WebRequest.Create("http://buypoe.com/external.php?type=RSS2&lastpost=true");
        WebResponse response = request.GetResponse();
        StringBuilder sb = new StringBuilder("");
        System.IO.StreamReader rssStream = new System.IO.StreamReader(response.GetResponseStream(), System.Text.Encoding.GetEncoding("utf-8"));
        XmlDocument rssDoc = new XmlDocument();
        rssDoc.Load(rssStream);
        XmlNodeList rssItems = rssDoc.SelectNodes("rss/channel/item");
        for (int i = 0; i < 5; i++)
            {
                XmlNode rssDetail;
                rssDetail = rssItems.Item(i).SelectSingleNode("dc:creator");
                if (rssDetail != null)
                {
                    user = rssDetail.InnerText;
                }
                else
                {
                    user = "";
                }
            }

I understand that I need to define the namespace, but am unsure how to do this. Help would be appreciated.