'home' link in breadcrumb has one too many '/'

Server config: Windows 2000 Server ; Apache 2.0.63 ; PHP 5.2.5 ; MySQL 5.0.45 ; Drupal 5.7.

I noticed a problem on 2 different drupal installs with Article 2.4.

Site 1 at URL http://www.example.com
When consulting http://www.example.com/article/1 , the HTML code of the breadcrumb reads:
<div class="breadcrumb"><a href="//">Home</a> » <a href="/article/">Articles</a> » <a href="/article/1" class="active">Article xx</a></div>

Site 2 run in a subdirectory at URL http://www.example.com/site2
When consulting http://www.example.com/site2/article/1 , the HTML code of the breadcrumb reads:
<div class="breadcrumb"><a href="/site2//">Home</a> » <a href="/site2/article/">News Archives</a> » <a href="/site2/article/13" class="active">Article xx</a></div>

As you will notice there are 2 trailing slashes ending the <a href> link to the 'Home' page in the breadcrumb.

I checked the settings.php file for both sites, and in each case the $base_url parameter is correctly configured (no trailing slash).

The breadcrumb displays the links correctly for the 'home' link in book pages (no double trailing slash). I do not have this problem anywhere outside the page displayed via the article module.

Can someone check and confirm if this is a bug in the module ? Or do I have a config problem on my sites ?