dropdown IE

HTML

<link rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap.min.css">
<script src="//netdna.bootstrapcdn.com/bootstrap/3.0.0/js/bootstrap.min.js"></script>
<nav id="navbar-example" class="navbar navbar-default navbar-static" role="navigation">
    <div class="navbar-header"> <a class="navbar-brand" href="#">Project Name</a>

    </div>
    <ul class="nav navbar-nav">
        <li class="dropdown"> <a href="#" role="button" class="dropdown-toggle" data-toggle="dropdown">Dropdown <b class="caret"></b></a>

            <ul class="dropdown-menu" role="menu">
                <li role="presentation"><a role="menuitem" tabindex="-1" href="http://twitter.com/fat">Action</a>
                </li>
                <li role="presentation"><a role="menuitem" tabindex="-1" href="http://twitter.com/fat">Another action</a>
                </li>
                <li role="presentation"><a role="menuitem" tabindex="-1" href="http://twitter.com/fat">Something else here</a>
                </li>
                <li role="presentation" class="divider"></li>
                <li role="presentation"><a role="menuitem" tabindex="-1" href="http://twitter.com/fat">Separated link</a>
                </li>
            </ul>
        </li>
        <li class="dropdown"> <a href="#" id="drop2" role="button" class="dropdown-toggle" data-toggle="dropdown">Dropdown 2 <b class="caret"></b></a>

            <ul class="dropdown-menu" role="menu" aria-labelledby="drop2">
                <li role="presentation" tabindex="1"><a role="menuitem" tabindex="-1" href="http://twitter.com/fat">Action</a>
                </li>
                <li role="presentation" tabindex="2"><a role="menuitem" tabindex="-1" href="http://twitter.com/fat">Another action</a>
                </li>
                <li role="presentation"><a role="menuitem" tabindex="-1" href="http://twitter.com/fat">Something else here</a>
                </li>
                <li role="presentation" class="divider"></li>
 ...