I use Visionary theme in WP 2.7.1.
This is what I get as the permalink for the individual comment:
That is, the comment number is missing.
The corresponding code in the theme is as follows:
<a class="permalink" href="#comment-<?php str_replace('&', '&', get_comment_ID()); ?>" title="<?php _e('Permalink to comment','visionary'); ?>"><?php _e('Permalink','visionary'); ?></a>