Trying To Fix A Simple ALT Tag Problem (Thanks To Anyone That Assists)

I have a (probably simple) question.

Our site is located: http://www.gunreviews.biz

On our opening page, we have the thumbnails that are of course 80 x 80 pixels. When you put your mouse over the top of them, they display an ALT Tag. Simple enough to understand so far.

Now, when you go to that page to view the post, for example:

http://www.gunreviews.biz/accessory-reviews/novatac-edc-120p-review/

You will see a larger image at the top, its dimensions being 581 x 180

The problem is that no ALT Tag is working when we mouse over the image.

The front page is obviously edited on the index.php page and the post page is edited on the single.php page.

The code does look the same for both, but it does not work in this theme by default. Can anyone tell me what code needs to be fixed on the single page so that it displays the ALT Tag like it does on the front page?

Thanks to anyone that takes a moment to post a fix.

The code that appears to handle this from the index.php page is:

<a title="<?php the_title(); ?>" href="<?php the_permalink() ?>" rel="bookmark"><img src="<?php echo bloginfo('template_url'); ?>/thumb.php?src=<?php echo get_post_meta($post->ID, "thumb", $single = true); ?>&h=<?php echo $thumbheight ?>&w=<?php echo $thumbwidth ?>&zc=1&q=80" alt="<?php the_title(); ?>" /></a>

The code that does not appear to be working at this time on the single.php page is:

<div id="main-post-image-container" class="box">
	<div class="main-post-image-inner">
		<img class="box" src="<?php echo bloginfo('template_url'); ?>/thumb.php?src=<?php echo get_post_meta($post->ID, "thumb", $single = true); ?>&h=180&w=581&zc=1&q=80" alt="<?php the_title(); ?>" />
		<h3><span>Sitewide Article Views: <?= simplehitcounter_hit(); ?></span>Posted on <?php the_time('l, F jS, Y') ?></h3>
	</div>
</div>