双滚动条，但没有滚动

我有以下的CSS和HTML，它导致Firefox（显示两个滚动条（右2和底部2），但它们看起来被禁用，即使最小化页面不滚动双滚动条，但没有滚动

* { 
    font-family:'Helvetica Neue','Helvetica','Arial'; 
    font-size:12px; 
    color:#333; 
} 

html, body { 
    background:#e0e0e0; 
    height:100%; 
    background-image: url('/images_/backgrounds/background.jpg'); 
    background-repeat: repeat-x;  
    margin:0; 
    overflow: scroll; 
} 

/***************** main wrapper and content ********************/ 

#wrapper { 
    text-align: left; 
    margin: 0px auto; 
    /*padding: 0px 12px 0px 12px;*/ 
    border:0; 
    width: 960px; 
    height: 100%; 
    background-image: url('/images_/backgrounds/content_shadow.png'); 
    background-repeat: repeat-y; 
} 

#content { 
    float: left; 
    width: 100%; 
    padding:85px 16px 10px 18px; 
} 

#topbar { 
    width:100%; 
    height:42px; 
    margin:0; 
    padding:0; 
    background: #0066cc; 
    /* make top bar stick to the top of browser */ 
    position:fixed; 
    z-index:800; 
    /*Making sure it sticks to left of window in IE7*/ 
    top:0; 
    left:0; 
    float:left; 
    -webkit-box-shadow: 0 8px 6px -6px #666; 
    -moz-box-shadow: 0 8px 6px -6px #666; 
    box-shadow: 0 8px 6px -6px #666; 
} 

#top_blur { 
    width:940px; 
    margin:0 auto; 
    height:70px; 
    z-index:1; 
    /*background-color: red; 
    background-repeat: no-repeat;*/ 
    position:fixed; 
} 

.header { 
    width:940px; 
    margin:0 auto; 
    position: fixed; 
    /*top: -70px;*/ 
    z-index: 801; 
}

这是HTML

<body><div id="wrapper"> 
<div id="topbar"></div> 
<div id="top_blur"><img src=/images_/backgrounds/top_blur.png></div> 
<div class="header"> header content here</div></div>

的