MS - Refresh w/ optgroups bug?

1.10

HTML

<script src="http://github.com/ehynds/jquery-ui-multiselect-widget/raw/1.10/src/jquery.multiselect.js"></script>
<script src="https://raw.github.com/ehynds/jquery-ui-multiselect-widget/master/src/jquery.multiselect.filter.js"></script>
<link rel="stylesheet" href="http://erichynds.com/examples/jquery-ui-multiselect-widget/jquery.multiselect.css">
<link rel="stylesheet" href="http://erichynds.com/examples/jquery-ui-multiselect-widget/jquery.multiselect.filter.css">
<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.14/themes/redmond/jquery-ui.css">
<form>
   
    
    <select id="try" name="test" style="width: 300px" multiple>
       
            <option value="foo1">foo</option>
            <option value="bar1">bar</option>
            <option value="baz1">baz</option>
       
            <option value="foo2">foo</option>
            <option value="bar2">bar</option>
            <option value="baz2">baz</option>
        
    </select>

        
    <select name="test" style="width: 300px" multiple>
        <option value="foo">foo</option>
        <option value="bar">bar</option>
        <option value="baz">baz</option>
    </select>
    
        
    <select name="test" style="width: 300px" multiple>
        <option></option>
        <option value="foo">foo</option>
        <option value="bar">bar</option>
        <option value="baz">baz</option>
    </select>
        
    <p><input type="button" value="refresh()"></p>
</form>

JavaScript

var selects = $("select").multiselect();

$("[type='button']").click(function(){
    selects.multiselect("refresh");
})


$("select").multiselect("widget").find(":checkbox[value='baz']").each(function(){
    alert("found!");
   this.click();
});