You can try another way to add items in navbar as many as you required. Let me explain.
HTML of navbar is as fallows.
Add this Jquery function to remove class ui-grid-a from
that limits the number of items on navbar.
$(document).ready(function() {
$("#my-navbar > ul").removeClass("ui-grid-a");
});
Now you will have to calculate the width of each navbar item OR you can set it manually. In this example we have 7 items to display on navbar and we want to divide the space equally to each item.
For a PHP page we will do this.
For static HTML pages you can set the width of each item manually
Thats it :)
I have used it for me and it works fine.