Pagination wont work

i have a page template that query posts from a category and display it..
Ive installed a wp-pagenavi plugin to paginate the queried category posts.. but it wont work also i have a previous_posts_link() in case but still wont work.. upon clicking the link the posts dont change..
here is the code i use.. please help me im just a noob in wordpress php programmin… i just copy this php codes from the web and hope someone can help me on this.. thank you very much in advance…

<?php
/*
Template Name: PageOfPosts
Modified for iNove Theme in WP 2.8 by Robert Savage.
*/
wp_enqueue_script( ‘jquery’ );
get_header();

$options = get_option(‘inove_options’);
if (function_exists(‘wp_list_comments’))
{
add_filter(‘get_comments_number’, ‘comment_count’, 0);
}

// if this is a certain page ID, then set the category to a specific category id.
if (is_page(’19’) )
{
$cat = array(4);
}

else
{
$cat = ”;
}

$showposts = 3; // -1 shows all posts
$do_not_show_stickies = 1; // 0 to show stickies
$args=array(
‘category__in’ => $cat,
‘showposts’ => $showposts,
‘caller_get_posts’ => $do_not_show_stickies,

);
$my_query = new WP_Query($args);

?>

<?php
//get_sidebar();
?>
<script type=”text/javascript”>

jQuery(document).ready(function($) {
// $() will work as an alias for jQuery() inside of this function

$(‘.intro’).click(function() {

$(this).animate({
height : ‘toggle’,
opacity: ‘toggle’
}, 500)
.parent(‘.content’).children(‘.whole’).animate({
height : ‘toggle’,
opacity: ‘toggle’

}, 500);

});
$(‘.whole’).click(function() {

$(this).parent(‘.content’).children(‘.whole’).animate({
height : ‘toggle’,
opacity: ‘toggle’

}, 500)

.parent(‘.content’).children(‘.intro’).animate({
height : ‘toggle’,
opacity: ‘toggle’
}, 500);

});

});

</script>

<div id=”primary” class=”hfeed” style=”width: 720px;”>
<?php if( $my_query->have_posts() ) : ?>

<?php while ($my_query->have_posts()) : $my_query->the_post(); ?>
<?php

//necessary to show the tags
global $wp_query;
$wp_query->in_the_loop = true;
?>

<div <?php post_class() ?> id=”post-<?php the_ID(); ?>”>

<div class=”post-thumbnail-div”>
<?php the_post_thumbnail(‘post-thumbnails’); ?>
</div>

<div class=”post-entry-div” style=”width: 600px;”>

<h3>
<!– THE TITLE –>
” rel=”bookmark”><?php the_title(); ?>
</h3>

<div class=”info”>
<span class=”date”><?php the_time(__(‘F jS, Y’, ‘inove’)) ?></span>
<?php if ($options[‘author’]) : ?><span class=”author”><?php the_author_posts_link(); ?></span><?php endif; ?>
<?php edit_post_link(__(‘Edit’, ‘inove’), ‘<span class=”editpost”>’, ‘</span>’); ?>
<span class=”comments”><?php comments_popup_link(__(‘No comments’, ‘inove’), __(‘1 comment’, ‘inove’), __(‘% comments’, ‘inove’), ”, __(‘Comments off’, ‘inove’)); ?></span>
<div class=”fixed”></div>
</div>

<div class=”content”>

<?php //the_content(__(‘CONTINUE READING->’, ‘inove’)); ?>
<div class=”intro”><?php echo content(’50’); ?></div>
<div class=”whole”><?php the_content(); ?></div>

>Read More

<div class=”fixed”></div>
</div>

<div class=”under”>
<span class=”date”>Posted at <?php the_time(‘F j, Y’); ?> at <?php the_time(‘g:i a’); ?> </span>
<span class=”comments”><?php comments_popup_link(__(‘No comments’, ‘inove’), __(‘1 comment’, ‘inove’), __(‘% comments’, ‘inove’), ”, __(‘Comments off’, ‘inove’)); ?></span>
<div class=”fixed”></div>
</div>

</div>

</div>

<?php endwhile; ?>

<div id=”pagenavi”>
<?php
kriesi_pagination(6,6);

?>
<div class=”fixed”></div>
</div>

<?php else : ?>

<div class=”errorbox”>
<?php _e(‘Sorry, no posts matched your criteria.’, ‘inove’); ?>
</div>

<?php endif; ?>

</div>

<?php get_footer(); ?>