I can't submit on IE8 With Image button
===

I click an image to choose file , but when i click submit button it not working ! (input file get clear)
i click 'browse' of file input => submit ok 

My code : 

        
        <script type="text/javascript">
        function haha(){
        	document.getElementById("picField").click();
        }
        </script>
    
    <form action="url"  enctype="multipart/form-data" method="post">
       <img src="/images/common/btn_submit_o.gif" onclick="haha();" />
       <input type="file" name="picField" id="picField" >
       <input type="submit" />
    </form>



