diff -u b/project_issue.module b/project_issue.module
--- b/project_issue.module
+++ b/project_issue.module
@@ -1517,9 +1517,8 @@
     if (!module_exists('comment_easy_reply')) {
       $uri = entity_uri('comment', $comment);
       $uri['options'] += array('attributes' => array('class' => 'permalink', 'rel' => 'bookmark'));
-
-      // Use the thread as the link text for comment number. Replace the permalink.
-      $thread = implode('.', array_map('vancode2int', explode('.', substr($comment->thread, 0, -1))));
+      // Use the thread as the link text for comment number.
+      $thread = project_issue_get_comment_thread_id($comment);
       $variables['permalink'] = l('#' . $thread, $uri['path'], $uri['options']);
     }
 
@@ -1531,6 +1530,21 @@
 }
 
 /**
+ * Return the thread identifier for a given comment.
+ *
+ * @param stdObj $comment
+ *   A fully-loaded comment entity object, as returned by comment_load().
+ *
+ * @return string
+ *   The sequential thread ID for the comment in a given issue. This is the
+ *   per-issue human-readable sequential comment number, starting from 1, not
+ *   the site-wide unique comment ID.
+ */
+function project_issue_get_comment_thread_id($comment) {
+  return implode('.', array_map('vancode2int', explode('.', substr($comment->thread, 0, -1))));
+}
+
+/**
  * @defgroup project_issue_solr Project Issue ApacheSolr integration
  * @{
  */
@@ -1823,7 +1837,7 @@
     'cid' => array(
       'title' => t('Comment ID'),
       'sort' => 'numeric',
-      'formatter' => 'project_issue_generate_cid_jumplink',
+      'formatter' => 'project_issue_generate_file_jumplink',
     ),
   );
 }
@@ -1984,20 +1998,23 @@
  *     the instance definition. Notable keys include the name of the formatter
  *     (in 'type') and the array of formatter settings (in 'settings').
  *
- * @return array or string
- *   A render array defining the table cell contents for this file/metadata
- *   combination, or alternatively an html string defining the actual rendered
- *   output.
+ * @return string
+ *   The HTML string for a "jumplink" to the place where a given file was
+ *   attached to an issue. Generally, this will link to the comment that was
+ *   auto-generated when an issue was attached, although for files attached to
+ *   the initial revision of an issue this will just link to the node body.
  */
-function project_issue_generate_cid_jumplink($item, $context) {
+function project_issue_generate_file_jumplink($file, $context) {
   // Generate formatted 'Comment ID' jumplinks for a file, based on the 'cid'
   // metadata property.
   $entity = $context['entity'];
-  if (empty($item['cid'])) {
+  if (empty($file['cid'])) {
     $data = l('none', 'node/' . $entity->nid, array('fragment' => 'content'));
   }
   else {
-    $data = l('#' . comment_get_display_ordinal($item['cid'], $entity->type), 'node/' . $entity->nid, array('fragment' => 'comment-' . $item['cid']));
+    $comment = comment_load($file['cid']);
+    $thread = project_issue_get_comment_thread_id($comment);
+    $data = l('#' . $thread, 'node/' . $entity->nid, array('fragment' => 'comment-' . $file['cid']));
   }
   return $data;
 }