(function($) {
	$.extend({
		/**
		 * appends a set of parameters to a given url. 
		 * usage: url = $.urlAppend(url, name1, val1, name2, val2,...);
		 * the additional parameter count must be even (there must be a 
		 * value for each name). otherwise, the last parameter name will be 
		 * omitted in the returned URL as well.   
		 */
		urlAppend: function(url /*, arguments[1...]*/) {
			var containsQuestionMark = (url.indexOf("?") > -1);
			var end = Math.floor((arguments.length+1)/2);
			for (var i = 1 ; i < end ; i++) {
			 	url += containsQuestionMark ? "&" : "?";
			 	url += arguments[2*i-1];
			 	url += "=";
			 	url += encodeURIComponent(arguments[2*i]);
			 	containsQuestionMark = true;
			}
			return url;
		}
	});
})(jQuery);