var zIndexBak = 0;
var highIndex = 19000;
var cnt = 0;

function getHighZIndex(obj) {
  if (obj) {
      zIndexBak = obj.style.zIndex;

      if (navigator.appName=='Microsoft Internet Explorer') {
    	  obj.style.setAttribute("z-index", highIndex+cnt, false);
    	  obj.style.setAttribute("zIndex", highIndex+cnt, false);
    	  obj.parentNode.parentNode.style.setAttribute("z-index", highIndex+cnt, false);
    	  obj.parentNode.parentNode.style.setAttribute("zIndex", highIndex+cnt, false);
      } else {
          obj.style.zIndex = highIndex+cnt;
    	  obj.parentNode.parentNode.style.zIndex = highIndex + cnt;
      }
      cnt++;
  }
}

function looseHighZIndex(obj) {
  if (obj) {
      if (zIndexBak>=highIndex || zIndexBak<=0) zIndexBak = 1000;
      if (navigator.appName == 'Microsoft Internet Explorer') {
        	  obj.style.setAttribute("z-index", zIndexBak, false);
        	  obj.style.setAttribute("zIndex", zIndexBak, false);  
        	  obj.parentNode.parentNode.style.setAttribute("z-index", zIndexBak, false);
        	  obj.parentNode.parentNode.style.setAttribute("zIndex", zIndexBak, false);  
      } else {
        	  obj.style.zIndex = zIndexBak;  
        	  obj.parentNode.parentNode.style.zIndex = zIndexBak;
      }
  }
}