Thumbnail not showing in sidebar

Hi!

I have a small problem with my sidebar thumbnail posts. I guess it’s an issue of the CSS but i don’t know what is exactly. It’s about the auto-resize of them. In the #content works perfectly but with the same values it doesn’t work in the #sidebar.

This is the code i’ve put in my sidebar:

<li><a href="<?php the_permalink(); ?>"><?php dp_attachment_image($post->ID, 'thumbnail', 'alt="' . $post->post_title . '"'); ?></a><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></li>

And this is the dp_attachment_image function (in functions.php):

# Displays post image attachment (sizes: thumbnail, medium, full)
function dp_attachment_image($postid=0, $size='thumbnail', $attributes='') {
	if ($postid<1) $postid = get_the_ID();
	if ($images = get_children(array(
		'post_parent' => $postid,
		'post_type' => 'attachment',
		'numberposts' => 1,
		'post_mime_type' => 'image',)))
		foreach($images as $image) {
			$attachment=wp_get_attachment_image_src($image->ID, $size);
			?><img src="<?php echo $attachment[0]; ?>" <?php echo $attributes; ?> /><?php
		}
}

This is the CSS that works in the index for a resize of the thumbnail (150×150 default) to 94px width:

#content .post img {
border:3px solid #EFEFEF;
float:left;
margin:2px 8px 4px 0;
width:94px;
}

I’ve tried with #sidebar .post img and same values but it shows the thumb in 150×150 as it doesn’t take the css.

Thanks for ur help!