getRelativeOffset-jquery-plugin.js

(function($){

	$.fn.getRelativeOffset = function(name){
		var elem = this[0],
			top = 0,
			left = 0;

		// require relative
		if($(name).css("position") != "relative")
			$(name).css("position", "relative")

		while(elem){
			left += elem.offsetLeft;
			top += elem.offsetTop;

			if(elem.offsetParent === $(name)[0])
				break;

			elem = elem.offsetParent;
		}

		return {
			left : left, top : top
		};
	}

})(jQuery);