try this:
function sortList() {
var ul = $('#ajaxInner');
var li = ul.children("li");
li.detach().sort(function(a, b) {
var date1 = new Date (new Date().toDateString() + ' ' + $(a).children('span.transactTime').text().substr(0,5))
var date2 = new Date (new Date().toDateString() + ' ' + $(b).children('span.transactTime').text().substr(0,5))
var result = (date1 < date2) ? -1 : (date1 > date2) ? 1 : 0
return result;
});
ul.append(li);
}