jQuery ColorBox插件在ie7下弹出框下面的边框显示不全，少一截？

  弹出框在ie8和firefox显示都完全，就是在ie7，ie6下是下面的边框少一截，怎么改能显示完全？望指教css里是这么写的
#colorbox, #cboxOverlay, #cboxWrapper{position:absolute; top:0; left:0; z-index:9999; overflow:hidden;}
#cboxOverlay{position:fixed; width:100%; height:100%;}
#cboxMiddleLeft, #cboxBottomLeft{clear:left;}
#cboxContent{position:relative;}
#cboxLoadedContent{overflow:auto;}
#cboxTitle{margin:0;}
#cboxLoadingOverlay, #cboxLoadingGraphic{position:absolute; top:0; left:0; width:100%; height:100%;}
#cboxPrevious, #cboxNext, #cboxClose, #cboxSlideshow{cursor:pointer;}
.cboxPhoto{float:left; margin:auto; border:0; display:block;}
.cboxIframe{width:100%; height:100%; display:block; border:0;}
#cboxOverlay{background:#000;}
#colorbox{}
    #cboxContent{margin-top:20px;}
        .cboxIframe{background:#fff;}
        #cboxError{padding:50px; border:1px solid #ccc;}
        #cboxLoadedContent{border:5px solid #000; background:#fff;}
        #cboxTitle{position:absolute; top:-20px; left:0; color:#ccc;}
        #cboxCurrent{position:absolute; top:-20px; right:0px; color:#ccc;}
        #cboxSlideshow{position:absolute; top:-20px; right:90px; color:#fff;}
        #cboxPrevious{position:absolute; top:50%; left:5px; margin-top:-32px; background:url(images/controls.png) no-repeat top left; width:28px; height:65px; text-indent:-9999px;}
        #cboxPrevious:hover{background-position:bottom left;}
        #cboxNext{position:absolute; top:50%; right:5px; margin-top:-32px; background:url(images/controls.png) no-repeat top right; width:28px; height:65px; text-indent:-9999px;}
        #cboxNext:hover{background-position:bottom right;}
        #cboxLoadingOverlay{background:#000;}
        #cboxLoadingGraphic{background:url(images/loading.gif) no-repeat center center;}
        #cboxClose{position:absolute; top:5px; right:5px; display:block; background:url(images/controls.png) no-repeat top center; width:38px; height:19px; text-indent:-9999px;}
        #cboxClose:hover{background-position:bottom center;}html里写
$.colorbox({html:message,open:true,width:'400px',height:'200px',opacity:"0"});
jQuery ColorBox插件在这里
http://jacklmoore.com/colorbox/