jQuery dual multiple select combo box
<p>i have a function that brings value from 1 combo box to the other.</p>

<pre><code>product.bind('click', function() 
        {
            var t = ($(this).hasClass('prevbtn'))? 0 : 1;
            if(t)
            {
                unsel.find('option').each(function()
                {
                    if($(this).is(':selected')) 
                    {
                        jQuery(this).attr('selected',true);
                        var op = sel.find('option:first-child');
                        sel.append($(this));
                    }
                }); 
            } 
            else 
            {
                sel.find('option').each(function()
                {
                    if($(this).is(':selected')) 
                    {
                        jQuery(this).attr('selected',false);
                        unsel.append($(this));
                    }
                });
            }
</code></pre>

<p>is there any way to pass value from unsel box to sel box without removing from unsel box? what i want to do is people are able to pass as many unsel values into sel box as many as they want to.</p>

<p>many thanks!</p>
