I have tried long and hard to find a solution to this problem with IE6. I'm implementing the main menu displayed on the CSS Friendly adapters website.  Its obvious that when a client hovers through the menu levels that each change in location is requiring another download of the arrow images and background images, instead of using the cached images. Firefox of course has no problem at all with this, but IE 6 fumbles around.  The funny thing is CSSAdapters source works fine, not display problems.  I'm starting to believe that the main problem is the arrows, the active and inactive arrows to indicate that there are more elements inside an element.  The menu that the CSS Friendly adapters website uses only has one element in the 2nd tier that contains a 3rd tier element.  In my case, all the 2nd tier elements have have a 3rd tier of elements and that are ~9 elements in the 2nd tier. 

So each time I hover around, even in the third tier, all the 2nd tier must redownload the background image for the for the selected element and all the 2nd tier arrows.... So,  is there a way around this while keeping the arrows and the background images?  Is there a way to force IE 6 to use the locally cached images?  I have even used MainMaster.css file int the css friendly web site's source and it still works fine, no obvious display problems.  But when I add a large about of elements to the 2nd tier of the site map with 3rd level elements it brings the same delayed display problem.  Can anyone help with this? Or is anyone else experiencing the same problem?  I have seen this problem posted in other forums but no real solution.

here is the generic web.sitemap file for the Css friendly website that will show the problem:

<siteMap xmlns="http://schemas.microsoft.com/AspNet/SiteMap-File-1.0" >
  <siteMapNode url="http://www.asp.net" title="ASP.NET Home" description="ASP.NET Home">
    <siteMapNode url="~/Default.aspx" title="Welcome" description="home page" />
    <siteMapNode title="Examples" description="a list of live examples">
      <siteMapNode url="~/Menu.aspx" title="Menu" description="live example of a Menu" />
      <siteMapNode url="~/TreeView.aspx" title="TreeView" description="live example of a TreeView" />
      <siteMapNode url="~/DetailsView.aspx" title="DetailsView" description="live example of a DetailsView" />
      <siteMapNode url="~/FormView.aspx" title="FormView" description="live example of a FormView" />
      <siteMapNode url="~/GridView.aspx" title="GridView" description="live example of a GridView" />
      <siteMapNode url="~/DataList.aspx" title="DataList" description="live example of a DataList" />
      <siteMapNode title="Membership9" description="membership examples">
        <siteMapNode url="~/Membership/Login1.aspx" title="Login" description="live example of a Login" />
        <siteMapNode url="~/Membership/ChangeP1assword.aspx" title="ChangePassword" description="live example of a ChangePassword" />
        <siteMapNode url="~/Membership/Passwor1dRecovery.aspx" title="PasswordRecovery" description="live example of a PasswordRecovery" />
        <siteMapNode url="~/Membership/CreateU1serWizard.aspx" title="CreateUserWizard" description="live example of a CreateUserWizard" />
        <siteMapNode url="~/Membership/LoginSta1tus.aspx" title="LoginStatus" description="live example of a LoginStatus" />
      </siteMapNode>
      <siteMapNode title="Membership8" description="membership examples">
        <siteMapNode url="~/Membership/Login.as2px" title="Login" description="live example of a Login" />
        <siteMapNode url="~/Membership/ChangePa2ssword.aspx" title="ChangePassword" description="live example of a ChangePassword" />
        <siteMapNode url="~/Membership/Password2Recovery.aspx" title="PasswordRecovery" description="live example of a PasswordRecovery" />
        <siteMapNode url="~/Membership/CreateUse2rWizard.aspx" title="CreateUserWizard" description="live example of a CreateUserWizard" />
        <siteMapNode url="~/Membership/LoginStat2us.aspx" title="LoginStatus" description="live example of a LoginStatus" />
      </siteMapNode>
      <siteMapNode title="Membership7" description="membership examples">
        <siteMapNode url="~/Membership/Logi3n.aspx" title="Login" description="live example of a Login" />
        <siteMapNode url="~/Membership/Chang3ePassword.aspx" title="ChangePassword" description="live example of a ChangePassword" />
        <siteMapNode url="~/Membership/Passw3ordRecovery.aspx" title="PasswordRecovery" description="live example of a PasswordRecovery" />
        <siteMapNode url="~/Membership/Creat3eUserWizard.aspx" title="CreateUserWizard" description="live example of a CreateUserWizard" />
        <siteMapNode url="~/Membership/LoginS3tatus.aspx" title="LoginStatus" description="live example of a LoginStatus" />
      </siteMapNode>
      <siteMapNode title="Membership6" description="membership examples">
        <siteMapNode url="~/Membership/Login.4aspx" title="Login" description="live example of a Login" />
        <siteMapNode url="~/Membership/ChangePa4ssword.aspx" title="ChangePassword" description="live example of a ChangePassword" />
        <siteMapNode url="~/Membership/Password4Recovery.aspx" title="PasswordRecovery" description="live example of a PasswordRecovery" />
        <siteMapNode url="~/Membership/CreateUse4rWizard.aspx" title="CreateUserWizard" description="live example of a CreateUserWizard" />
        <siteMapNode url="~/Membership/LoginStat4us.aspx" title="LoginStatus" description="live example of a LoginStatus" />
      </siteMapNode>
      <siteMapNode title="Membership0" description="membership examples">
        <siteMapNode url="~/Membership/Login.a5spx" title="Login" description="live example of a Login" />
        <siteMapNode url="~/Membership/ChangeP5assword.aspx" title="ChangePassword" description="live example of a ChangePassword" />
        <siteMapNode url="~/Membership/Passwor5dRecovery.aspx" title="PasswordRecovery" description="live example of a PasswordRecovery" />
        <siteMapNode url="~/Membership/CreateU5serWizard.aspx" title="CreateUserWizard" description="live example of a CreateUserWizard" />
        <siteMapNode url="~/Membership/LoginSta5tus.aspx" title="LoginStatus" description="live example of a LoginStatus" />
      </siteMapNode>
      <siteMapNode title="Membership1" description="membership examples">
        <siteMapNode url="~/Membership/Login.a6spx" title="Login" description="live example of a Login" />
        <siteMapNode url="~/Membership/ChangePa6ssword.aspx" title="ChangePassword" description="live example of a ChangePassword" />
        <siteMapNode url="~/Membership/PasswordR6ecovery.aspx" title="PasswordRecovery" description="live example of a PasswordRecovery" />
        <siteMapNode url="~/Membership/CreateUse6rWizard.aspx" title="CreateUserWizard" description="live example of a CreateUserWizard" />
        <siteMapNode url="~/Membership/LoginStat6us.aspx" title="LoginStatus" description="live example of a LoginStatus" />
      </siteMapNode>
      <siteMapNode title="Membership2" description="membership examples">
        <siteMapNode url="~/Membership/Login.a7spx" title="Login" description="live example of a Login" />
        <siteMapNode url="~/Membership/ChangePa7ssword.aspx" title="ChangePassword" description="live example of a ChangePassword" />
        <siteMapNode url="~/Membership/Password7Recovery.aspx" title="PasswordRecovery" description="live example of a PasswordRecovery" />
        <siteMapNode url="~/Membership/CreateUs7erWizard.aspx" title="CreateUserWizard" description="live example of a CreateUserWizard" />
        <siteMapNode url="~/Membership/LoginSta7tus.aspx" title="LoginStatus" description="live example of a LoginStatus" />
      </siteMapNode>
      <siteMapNode title="Membership3" description="membership examples">
        <siteMapNode url="~/Membership/Login.a8spx" title="Login" description="live example of a Login" />
        <siteMapNode url="~/Membership/ChangeP8assword.aspx" title="ChangePassword" description="live example of a ChangePassword" />
        <siteMapNode url="~/Membership/Passwor8dRecovery.aspx" title="PasswordRecovery" description="live example of a PasswordRecovery" />
        <siteMapNode url="~/Membership/CreateU8serWizard.aspx" title="CreateUserWizard" description="live example of a CreateUserWizard" />
        <siteMapNode url="~/Membership/LoginSta8tus.aspx" title="LoginStatus" description="live example of a LoginStatus" />
      </siteMapNode>
      <siteMapNode title="Membership4" description="membership examples">
        <siteMapNode url="~/Membership/Login.a9spx" title="Login" description="live example of a Login" />
        <siteMapNode url="~/Membership/ChangePa9ssword.aspx" title="ChangePassword" description="live example of a ChangePassword" />
        <siteMapNode url="~/Membership/Password9Recovery.aspx" title="PasswordRecovery" description="live example of a PasswordRecovery" />
        <siteMapNode url="~/Membership/CreateUs9erWizard.aspx" title="CreateUserWizard" description="live example of a CreateUserWizard" />
        <siteMapNode url="~/Membership/LoginStat9us.aspx" title="LoginStatus" description="live example of a LoginStatus" />
      </siteMapNode>
    </siteMapNode>
    <siteMapNode title="Help" description="help and documentation">
      <siteMapNode url="~/WalkThru/WalkThrough.aspx" title="Tutorial" description="a tutorial or walk-through of how the sample kit is installed and used" />
      <siteMapNode url="~/WhitePaper.aspx" title="White Paper" description="white paper describing the architecture and theory behind this web site" />
      <siteMapNode url="http://forums.asp.net/1018/ShowForum.aspx" title="Forum" description="forum for asking questions and reporting bugs" />
    </siteMapNode>
  </siteMapNode>
</siteMap>

thanks for the help, and sorry for rambling