WP 1.5 also strips links out of archives. The problem is in the function that creates the shortened versions of your posts that show up in the archive. I got tired of it so I just hacked the code so that the full posts show in the archives. It really only requires replacing one line in archive.php
Just paste this code in place of line 42 (or thereabouts...it goes between the content div tags):
<?php the_content('Read the rest of this entry »'); ?>
The other advantage of this is that it allows you to direct people to a category and instead of getting an archive of that category with no pics and links, they get the whole deal.