li 列表中tel:10086 拨号没反应

如题，代码如下

                    <div class="mui-slider-cell mui-slider-handle">  
                        <div class="oa-contact-cell mui-table">  
                            <div class="oa-contact-avatar mui-table-cell">  
                                <img src="../images/60x60.gif" />  
                            </div>  
                            <div class="oa-contact-content mui-table-cell">  
                                <div class="mui-clearfix">  
                                    <h4 class="oa-contact-name">解缙</h4>  
                                    <span class="oa-contact-position mui-h6">文化部长</span>  
                                    <a href="tel:10086">10086</a>  
                                </div>  
                                <p class="oa-contact-email mui-h6">  
                                    chunyu@sina.com  
                                </p>  
                            </div>  
                        </div>  
                    </div>