HTTPrequest, cookie trouble

I use visual basic .net express edition 2008

I figured out how to do httprequests and how to login using them.
I tried to login onto http://www.lostpirates.co.uk this is the code:

Code:

---

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim postdata As String = "username=name & user_password=pass & op=login"
        '(Dim postdata As String = TextBox1.Text)
        Try
            Dim uri As New Uri("http://www.lostpirates.co.uk/modules.php?name=Your_Account")
            Dim text As String = ""
            'this part is for my own purposes
            'I used a textbox to try different postdata.
            'vbcrlf had to be added sometimes.
            For Each item As String In postdata.Split
                If item.ToLower = "vbcrlf" Then
                    text &= vbCrLf
                Else
                    text &= item
                End If
            Next
            'end of filtering vbcrlf, data is there.
            Dim data As String = text
            MsgBox(data)
            Dim request As HttpWebRequest = HttpWebRequest.Create(uri)
            request.UserAgent = "Mozilla/5.0 (Windows; U; Windows NT 6.0; nl; rv:1.9.1.3) Gecko/20090824 Firefox/3.5.3 (.NET CLR 3.5.30729)"
            request.KeepAlive = 30
            request.Method = WebRequestMethods.Http.Post
            request.ContentLength = data.Length
            request.ContentType = "application/x-www-form-urlencoded"
            request.Method = "POST"
            request.AllowAutoRedirect = False
            Dim writer As New StreamWriter(request.GetRequestStream())
            writer.Write(data)
            writer.Close()
            Dim response As HttpWebResponse = request.GetResponse()
            Dim reader As New StreamReader(response.GetResponseStream())
            Dim tmp As String = reader.ReadToEnd()
            response.Close()
            WebBrowser1.DocumentText = tmp
            MsgBox("Done request")
        Catch ex As Exception
            If ex.Message <> "" Then MsgBox("Error:" & vbCrLf & vbCrLf & ex.Message, MsgBoxStyle.Critical)
        End Try
    End Sub

---

But I get this error on the site:
"Cookie functions seem to be disabled. Please change your browser settings!"

How can I set a cookie container so I can login onto the site?

I tried a lot of things, such as cookiecontainer.
I tried googlin' it, but no helpfull info found :(

Please help :(

Please answer me, I really need to know how to set cookies for further purposes =(

Bump: