Node.tpl.php displaying empty Imagefields

Hi, I am having an Issue with linked Imagefields in Zen.

Even if there are no images loaded there are empty fields printed with a border and the node's title (shown on the screenshot: http://img15.imageshack.us/img15/194/fireshotcapture25artist.png).

At first, i thought it was a filefield/imagefield module malfunction and posted it here:
http://drupal.org/node/414944

The problem was considered not reproducable and so i built the site from scratch from an all fresh core and modules - this is what I am using (the only thing i used from the old site is the zen-subtheme):

---
Drupal 6.10
Content Construction Kit (CCK) 6.x-2.2
FileField 6.x-3.0
ImageField 6.x-3.0
ImageCache 6.x-2.0-beta9
Lightbox2 6.x-1.9

Zen sub-theme based on 6.x-1.0

2 imagecache presets: one for a partial preview image, another for the fullsize image (which is beeing linked to the preview via lightbox2)
---

I tested the filefields in the garland theme and here, they behave normal. So the problem of empty fields still showing must be related to my node.tpl.php syntax. This is what I use:

<?php
// Format the teaser image
if ($field_image_standard_thumb) {
  $image_standard_thumb = theme('imagecache', 'desaturate_-_resize_182px-110px', $field_image_standard_thumb[0]['filepath'], $node->title, $node->title);
}
?>

<div class="node">

	<?php // Teaser view
		if ($teaser): ?>
			
			<!-- Headline with link to node, followed by meta information (submitted and tags). 		
			<h2><a href="<?php print $node_url ?>" title="<?php print $title ?>"><?php print $title ?></a></h2>

			<div class="meta">
			
			<div class="meta">
				<span class="submitted"><?php print $submitted ?></span>
				<?php if ($terms): ?>
					<span class="terms"> in <?php print $terms ?></span>
				<?php endif; ?>
			</div>
			-->
			
			<div class="content">

			<?php if ($image_standard_thumb): ?>
				<!-- Div wrap with class for the nodelink.
				<div class="field field-type-image field-field-image-standard-thumb imagefield-nodelink">
				-->
				
				<div class="field field-type-image field-field-image-standard-thumb imagefield-gallerylink">
					<div class="field-items">
				
						<!-- Print the teaser image as a link to the full node.
						<?php
						print l($image_standard_thumb, 'node/'. $nid, array('html' => 'TRUE')) ?>
						-->

						<div class="field-item odd">
						<?php // Print the teaser image and link it to the fullsized image.
						print l($image_standard_thumb, imagecache_create_url('scale_500px_max', $field_image_standard_full[0]['filepath']), array('html' => 'TRUE', 'attributes' => array('class' => 'imagefield-field-image-standard-thumb', 'rel' => 'lightbox[]', 'title' => $node->field_image_standard_full[0]['data']['title']) ) ); ?>

						</div>
					</div>
				</div>
			<?php endif; ?>

			<?php print $node->teaser ?>
			
			<!-- Other content here -->

			</div>

	<?php // Full view
		else: ?>
			
			<!-- Meta information (submitted & tags).
			<div class="meta">
				<span class="submitted"><?php print $submitted ?></span>
				<?php if ($terms): ?>
					<span class="terms"> in <?php print $terms ?></span>
				<?php endif; ?>
			</div>
			-->
			
			<div class="content">

			<?php if ($image_standard_thumb): ?>
				<div class="field field-type-image field-field-image-standard-thumb imagefield-gallerylink">
					<div class="field-items">
						<div class="field-item odd">
						<?php // Print the teaser image and link it to the fullsized image.
						print l($image_standard_thumb, imagecache_create_url('scale_500px_max', $field_image_standard_full[0]['filepath']), array('html' => 'TRUE', 'attributes' => array('class' => 'imagefield-field-image-standard-thumb', 'rel' => 'lightbox[]', 'title' => $node->field_image_standard_full[0]['data']['title']) ) ); ?>
						</div>
					</div>
				</div>
			<?php endif; ?>

			<?php print $node->content['body']['#value'] ?>

			<!-- Other content here -->

			</div>

	<?php endif ?>

</div>

And this is the relevant HTML output for an empty field still displayed:

<div class="field field-type-image field-field-image-standard-thumb imagefield-gallerylink">
<div class="field-items">
<div class="field-item odd">
<a class="imagefield-field-image-standard-thumb lightbox-processed" title="" rel="lightbox[]" href="http://wp1121964.wp021.webpack.hosteurope.de/sites/default/files/imagecache/scale_500px_max/">
<img class="imagecache imagecache-desaturate_-_resize_182px-110px" title="Mimaku Spldat" alt="Mimaku Spldat" src="http://wp1121964.wp021.webpack.hosteurope.de/sites/default/files/imagecache/desaturate_-_resize_182px-110px/"/>
</a>
</div>
</div>
</div>

The problem is that the tpl.php is creating an path that ends where the actual file would be placed. Also i wonder why the alt text of the empty field prints the node title - i'd prefer to use the field's default alt text.

How would i have to modify the tpl.php to make the separate images still link via lightbox but only display when theres actually content to be displayed?