[Ready] Whats the right way for Block Titles Image Replacement ?

Heya :)

Whats the right way for Block Titles Image Replacement ?

for CSS it will looks so :

#block-menu-secondary-links h2 {
text-indent: -2000px; /*text is out of the way*/
background: url(image.gif) no-repeat right center; /* background image for title */
width:80px; /* substitute with actual width of image */
height:20px; /* substitute with actual height of image */
}

or in the block.tpl.php:

<?php
if ($block->module == 'user' && $block->delta == 1) {
        $block->subject = t('admin.jpg');
}
else if ($block->module == 'user' && $block->delta == 3) {
        $block->subject = t('Online.jpg');
}

... insert more Blocks ...

?>
<div class="block block-<?php print $block->module ?>" id="block-<?php print $block->module ?>-<?php print $block->delta ?>">
        <h2 class="title"><?php print $block->subject; ?></h2>
  <div class="content"><?php print $block->content; ?></div>
</div>

But whats the right way now ?

I changed my RSS-Feed Icon in the template php :

<?php
function skulltheme_feed_icon($url, $title) {
  $img_path = drupal_get_path('theme', 'skulltheme') .'/rss_feed.png';
  if ($image = theme('image', $img_path, t('Syndicate content'), $title)) {
    return '<a href="'. check_url($url) .'" class="feed-icon">'. $image .'</a>';
  }
}

Is it possible to make it working for Block titles too ?

Thx in advance

(Sorry for my broken english, i´m german ;) )