How to do redirect when crystalReportViewer "next page" is clicked?

Hi experts

My environment is VS2008 + .NET framework 2.0.

When end user clicks "next page" of CrystalReportViewer, if session is expired I need to tell the user to re-login.

    Private Sub Page_Init(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Init

        If Not Session("UserId") = 1 Then

            'hide crystal report viewer, and shows a "session timeout" linkbutton.
            CrystalReportViewer1.Visible = False
            LinkButton1.Visible = True

           'or simply redirect
            'response.redirect("login.aspx")

        End If
    End Sub

however both aproach doesn't work.

'hide crystal report viewer, and shows a "session timeout" linkbutton. -> page_init is invoked however the crystalreportviewer1 is still visible and linkbutton1 is not visible.

'redirect -> does not work with "redirect cannot work with callback" 

(it's probably because the callback is ajax etc, not a page postback)

How can I resolve this problem?

many thanks in advance