According to the upgrade guide for jquery-ui 1.9 tabs - http://jqueryui.com/upgrade-guide/1.9/#deprecated-add-and-remove-methods-and-events-use-refresh-method - when adding
After each tab addition you have to create a div for showing content like for creating tab number 2
tab number 2
$("div#tabs").append("");
check the fiddle http://jsfiddle.net/AJDLt/1/