How to fix IE6 Duplicate Content CSS Bug without using display:inline

The code I have is doubling content in IE6.  The reason is found here http://www.positioniseverything.net/explorer/dup-characters.html, and is because I am using display:block; and  display:hidden.    The solutions I find say to change any reference to display:block to display:inline.  My code is for a left navigation, and when moused over the content highlights, I need it to display block so that the text is highlighted as a block.  There are 3 levels,   NonGroup which means it is just a navigation item with no sub level links,  Group which means that is a navigation item that has sub level link that it will need to show when clicked, and Option which is the sub level links under Group.     There also is a javascript file that changes the class of the div to show or hide the options.  

My question is:  Is there a way to fix this bug other than changing my code to Display:inline?
I've included the code below:

CSS Code
---------------      
                .show {
            display:inline;
      }
      .hide {
            display:none;
      }
                .NonGroup {
            display: block;
            height: 100%;
            width: 155px;
            line-height: 18px;
            padding-left: 7px;
            padding-bottom:10px;
            text-decoration: none;
            font-weight:bold;
      }
            .NonGroup:hover {
                  text-decoration: none;
                  background-image:url(images/Design/highlight.GIF);
            }
      .Group {
            display: block;
            height: 100%;
            width: 155px;
            line-height: 18px;
            padding-left: 7px;
            padding-bottom:10px;
            text-decoration: none;
            font-weight:bold;
      }
            .Group:hover {
                  text-decoration: none;
                  background-image:url(images/Design/highlight.GIF);
            }
      .Option {
            display: block;
            height: 100%;
            width: 155px;
            line-height: 18px;
            padding-left: 7px;
            padding-bottom:10px;
            text-decoration: none;
            z-index:9999;      
      }
            .Option:hover {
                  background-image:url(images/Design/highlight.GIF);
                  text-decoration: none;
                  z-index:9999;
            }
HTML Code
----------------
  <a href="PublicReports.html" class="NonGroup" id="Public Reports">Public Reports</a>

  <a href="KeepingYouHealthy/default.html" onClick="expandCollapse('Keeping You Healthy')" class="Group" id="Keeping You Healthy">Keeping You Healthy</a>
        <div class="hide" id="Keeping You HealthySubs">
             <a href="GeneralHealthResources.html" class="Option" id="General Health Resources">General Health Resources</a>
              <a href="Prevention.html" class="Option" id="Prevention">Prevention</a>  
              <a href="ManagingYourHealth.html" class="Option" id="Managing Your Health">Managing Your Health</a>    
        </div>

JavaScript
---------------
function expandCollapse (navLevel) {
/*event fires when a group with sublevels is clicked, it either collapses or expands the clicked group*/

      //hide any expanded nav
            hideNav();

      //Now show the new nav level
            var subnavLevel = navLevel + "Subs" //Subs is added so that it expands the sub level and not the item sent
            var selectedNavLevel = document.getElementById(subnavLevel);
            

            if (selectedNavLevel.className=="hide") {
                  selectedNavLevel.className="show";
                  //Set expandCookie
                  createCookie('pwhExpandCookie', navLevel ,0);
            }      
      }
function hideNav(){
      //check to see if there currently is an expanded nav item and collapse it
            var expandedCookieName= readCookie('pwhExpandCookie');
            var navExpanded = document.getElementById(expandedCookieName +"Subs");
            if (navExpanded) {      
                  navExpanded.className="hide";
                  eraseCookie('pwhExpandCookie');
            }
}