var AD1_LINK = "http://www.cnun.com/irc/20-35/mirc.html"
var AD1_DESC = "中文聊天工具MIRC5.82"
var AD1_PIC  = "/images/banner/banner-mirc582.gif"

var AD2_LINK = "http://www.cnun.com/cartoon"
var AD2_DESC = "网络小人书"
var AD2_PIC  = "http://www.wzwtc.com/images/cartoon-banner2.gif"


var AD3_LINK = "http://www.cnun.com/cartoon"
var AD3_DESC = "网络小人书"
var AD3_PIC  = "http://www.wzwtc.com/images/cartoon-banner2.gif"



function GetBannerAd() {

  var i, ad_link, ad_desc, ad_pic, str

  i = Math.ceil(3 * Math.random())

  if (i == 1) {
    ad_link = AD1_LINK
    ad_desc = AD1_DESC
    ad_pic  = AD1_PIC
  }
  if (i == 2) {
    ad_link = AD2_LINK
    ad_desc = AD2_DESC
    ad_pic  = AD2_PIC
  }
  if (i == 3) {
    ad_link = AD3_LINK
    ad_desc = AD3_DESC
    ad_pic  = AD3_PIC
  }

  str = "<a href=" + ad_link 
  str += " onMouseOver=\"return showStatus('" + ad_desc + "')\" target=_blank>"
  str += "<img src=" + ad_pic + " width=468 height=60 border=1 "
  str += "alt='" + ad_desc + "'></a>"
  return str
}

function showStatus (msg) {
  window.status = msg
  return true
}