Wordpress functions.php - Annoying Unprogrammed Widget Zone Appears

PHP
1

Whatever number of Widget Zones I programme into my functions.php for my Wordpress Theme, when clicking on WP-ADMIN>>WIDGETS to define what is displayed where, I always get an additional Widget Zone listed.

i.e. If I define 4 Widget Zones, a Widget Zone appears in WP-ADMIN>>WIDGETS called ‘Sidebar 5’. if 5 Widget Zones, ‘Sidebar 6’ and so on.

Droppping something into ‘Sidebar X’ doesn’t display anything on the user-side page.

FUNCTIONS.PHP


<?php 

/*Define Widget Zones for displaying Plugins */

if ( function_exists('register_sidebar') ) 
{     
register_sidebar(array('name' => 'Front Page Only Top Right','before_widget' => '','after_widget' => '','before_title' => '<h3>','after_title' => '</h3>'));
register_sidebar(array('name' => 'All Pages Sidebar Top','before_widget' => '','after_widget' => '','before_title' => '<h3>','after_title' => '</h3>'));     
register_sidebar(array('name' => 'All Pages Sidebar Left','before_widget' => '','after_widget' => '','before_title' => '<h3>','after_title' => '</h3>')); 
register_sidebar(array('name' => 'All Pages Sidebar Right','before_widget' => '','after_widget' => '','before_title' => '<h3>','after_title' => '</h3>'));   
register_sidebar(array('name' => 'All Pages Sidebar Bottom','before_widget' => '','after_widget' => '','before_title' => '<h3>','after_title' => '</h3>'));    
}

remove_filter('get_the_excerpt', 'wp_trim_excerpt');
add_filter('get_the_excerpt', 'custom_trim_excerpt');

remove_filter('get_the_excerpt', 'wp_trim_excerpt');
add_filter('get_the_excerpt', 'custom_trim_excerpt');

function custom_trim_excerpt($text) { // Fakes an excerpt if needed
global $post;
	if ( '' == $text ) {
		$text = get_the_content('');

		$text = strip_shortcodes( $text );

		$text = apply_filters('the_content', $text);
		$text = str_replace(']]>', ']]>', $text);
		$text = strip_tags($text);
		$excerpt_length = apply_filters('excerpt_length', 90);
		$words = explode(' ', $text, $excerpt_length + 1);
		if (count($words) > $excerpt_length) {
			array_pop($words);
			array_push($words, '...');
			$text = implode(' ', $words);
		}
	}
	return $text;
}?>

and the snippet of code within relevant theme files


	<?php 	/* Widgetized sidebar, if you have the plugin installed. */
	if ( !function_exists('dynamic_sidebar') || !dynamic_sidebar(Y) ) : ?>
	<?php endif; ?>

Where Y is actually the corresponding number for the defined Widget Zone.

It’s driving me nuts! Anyone see someting glaringly obvious?