How to include jQuery UI on a page without PHP?
How about creating a 'scripts.js' file in your theme folder and then simply either add it in using the drupal_add_js method in template.php (the same method you are using above) or if it's something that's more global, include it in your theme's .info file. You will need to tweak the JQuery call according to 7 standards. I use both of these methods all the time and it works great.

So in your 'scripts.js' file you will have something like this:

(function ($) {
Drupal.behaviors.myTheme = {
attach: function(context, settings) {

// your custom JQuery here

}
};
})(jQuery);


... and then call that however you wish as I have described above. You can also have a look at this post: Managing JavaScript in Drupal 7