(function($j){
    $j.positionFixed = function(el){
        $j(el).each(function(){
            new fixed(this)
        })
        return el;                  
    }
    $j.fn.positionFixed = function(){
        return $j.positionFixed(this)
    }
    var fixed = $j.positionFixed.impl = function(el){
        this.target = $j(el).css('position','fixed')
        if(!this.ie6)return;
        this.bindEvent();
    }
    $j.extend(fixed.prototype,{
        ie6 : $.browser.msie && $.browser.version < 7.0,
        bindEvent : function(){
            var target=this.target;
            target
            .css('position','absolute')
            .basePos = {
                top: parseInt(target.css('top')) || 0,
                left: parseInt(target.css('left')) || 0
            }
            target.parents().each(function(){
                var o = $j(this);
                if (o.css('position') == 'relative') 
                    o.after(target)
            })
            $j(window).scroll(this.scrollEvent());
        },
        scrollEvent : function(){
            var target=this.target;
            return function(){
                target.css({
                    top: $j(document).scrollTop() + target.basePos.top,
                    left: $j(document).scrollLeft() + target.basePos.left
                })
            }
        }
    })
})(jQuery)