alpha numeric pager issues please help

 using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Xml;
using System.Data.OleDb;
using System.Drawing;


public partial class Glossario : System.Web.UI.Page
{
    protected void Page_Load(object sender, System.EventArgs e)
    {
        if ((Page.IsPostBack == false))
        {
            BindGrid();
        }
    }

    void BindGrid()
    {
        DataSet oDs = new DataSet();
        oDs.ReadXml((Request.PhysicalApplicationPath + "glossary.xml"));
        GridView1.DataSource = oDs;
        GridView1.DataBind();
    }

    protected void GridView1_PageIndexChanging(object sender, System.Web.UI.WebControls.GridViewPageEventArgs e)
    {
        GridView1.PageIndex = e.NewPageIndex;
        BindGrid();
    }

    protected void GridView1_RowCreated(object sender, GridViewRowEventArgs e)
    {
        if ((e.Row.RowType == DataControlRowType.Pager))
        {
            TableCell cell = e.Row.Cells[0];
            cell.ColumnSpan = 2;
            cell.Font.Size = 18;
            for (int index = 65; (index <= 90); index++)
            {
                LinkButton lb = new LinkButton();
                lb.Text = (char.ConvertFromUtf32(index) + "  ");
                lb.CommandArgument = lb.Text;
                lb.CommandName = "alphapage";
                cell.Controls.Add(lb);
            }
        }
    }

    protected void dvMergin_RowCommand(object sender, GridViewCommandEventArgs e)
    {

        if ((e.CommandName == "alphapage"))
        {
            string firstLetter = e.CommandArgument.ToString().Trim(); 
             DataSet oDs = new DataSet();
             oDs.ReadXml(Request.PhysicalApplicationPath + "glossary.xml");
            
             DataView filteredView = new DataView(oDs.Tables[0]);
             filteredView.RowFilter = "id LIKE '" + firstLetter + "%'";
            
             GridView1.DataSource = filteredView;
                
             GridView1.DataBind();
        }
    }
}

 <%@ Page Language="C#" AutoEventWireup="true" CodeFile="Glossario.aspx.cs" Inherits="Glossario" %>





    
        


    

    

        
         
            
            
            
            
            
            
            
            
            
            
          
             
        
        
    

    

 
 protected void GridView1_DataBound(object sender, EventArgs e)
    {
        SetPaging();
    }

    private void SetPaging()
    {
        GridViewRow row = GridView1.BottomPagerRow;
        int alphaStart = 65;

        for (int i = 1; i < GridView1.PageCount; i++)
        {
            LinkButton btn = new LinkButton();
            btn.CommandName = "Page";
           
            btn.CommandArgument = i.ToString();

            if (i == GridView1.PageIndex + 1)
            {
                btn.BackColor = Color.BlanchedAlmond;
            }

            btn.Text = Convert.ToChar(alphaStart).ToString();
            btn.ToolTip = "Page " + i.ToString();
            alphaStart++;
            PlaceHolder place = row.FindControl("PlaceHolder1") as PlaceHolder;
            place.Controls.Add(btn);

            Label lbl = new Label();
            lbl.Text = " ";
            place.Controls.Add(lbl);
        }
       
    }