IE下，同时放置多个SwfUpload Flash上传插件，有的不显示

SWFUpload.prototype.getFlashHTML = function () {
     // Flash Satay object syntax: http://www.alistapart.com/articles/flashsatay
     var myclass="";
     if(window.hasOwnProperty("ActiveXObject")){
         myclass='classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000"';
     }
     
     return ['<object '+myclass+'  id="', this.movieName, '" type="application/x-shockwave-flash" data="', this.settings.flash_url, '" width="', this.settings.button_width, '" height="', this.settings.button_height, '" class="swfupload">',
        '<param name="wmode" value="opaque"/>',
        '<param name="movie" value="', this.settings.flash_url, '" />',
        '<param name="quality" value="high" />',
        '<param name="menu" value="false" />',
        '<param name="allowScriptAccess" value="always" />',
        '<param name="flashvars" value="' + this.getFlashVars() + '" />',
        '</object>'].join("");
    };