function initMainNav()
{
            //////////mouseover////////
            $('#main-nav>ul>li>a>img').mouseover(function(){
                        var overImg = $(this).attr('src');
                        //affect only if this is not selected
                        if(overImg.indexOf('sel') < 0)
                        {
                                overImg = overImg.slice(0, overImg.indexOf('.png'));
                                $(this).attr('src', overImg + '-over.png');
                                
                        }
            });
                        
            //////////mouseout////////
            $('#main-nav>ul>li>a>img').mouseout(function(){
                        var overImg = $(this).attr('src');
                        //affect only if this is not selected
                        if(overImg.indexOf('sel') < 0)
                        {
                                overImg = overImg.slice(0, overImg.indexOf('-over.png'));
                                $(this).attr('src', overImg + '.png');
                        }
            });
}