Dann hast du wohl etwas falsch gemacht.
Ich komm aber einfach nicht drauf was...
div#nav {font-family:verdana; font-size:9pt; width: 129px; float:left; margin-top: 20px;}
div#nav ul {margin-left:-2 px; margin-top: 0; padding:0; width: 129px; background: #f0f0f5; border: 1px solid #403;z-index:1;}
div#nav li {position:relative; list-style: none; margin:0; border: 1px solid #CCC; z-index:1;}
div#nav li:hover {background: #ffffff;}
div#nav li.sub {background: url(pics_navi/pf_re2.gif) 98% 50% no-repeat;}
div#nav li.sub:hover {background-color: #F0F809;}
div#nav li a {display:block; padding: 0.5em 0 0.25em 0.5em; text-decoration:none;}
div#nav>ul a {width: auto;}
div#nav ul ul {position:absolute; top:-1px; left: 128px; width:220px; display:none; z-index:1;}
div#nav ul.level1 li.sub:hover ul.level2,
div#nav ul.level2 li.sub:hover ul.level3 {display:block;}
div#nav ul.level3 {position:absolute; top:-1px; left:219px; margin-top: -1px;}
Kannst du da nen Fehler entdecken??