=== modified file 'modules/comment.module'
--- modules/comment.module	
+++ modules/comment.module	
@@ -120,20 +120,29 @@
 
     $items[] = array('path' => 'admin/comment/configure/settings', 'title' => t('settings'),
       'type' => MENU_DEFAULT_LOCAL_TASK, 'weight' => -10);
-
-    $items[] = array('path' => 'comment/delete', 'title' => t('delete comment'),
-      'callback' => 'comment_delete', 'access' => $access, 'type' => MENU_CALLBACK);
-
-    $access = user_access('post comments');
-    $items[] = array('path' => 'comment/edit', 'title' => t('edit comment'),
-      'callback' => 'comment_edit', 'access' => $access, 'type' => MENU_CALLBACK);
   }
   else {
-    if (arg(0) == 'comment' && arg(1) == 'reply' && is_numeric(arg(2))) {
-      $node = node_load(arg(2));
-      if ($node->nid) {
-        $items[] = array('path' => 'comment/reply', 'title' => t('reply to comment'),
-          'callback' => 'comment_reply', 'access' => node_access('view', $node), 'type' => MENU_CALLBACK);
+    if (arg(0) == 'comment' && is_numeric(arg(2))) {
+      if (arg(1) == 'delete') {
+        $comment_exists = db_result(db_query("SELECT 1 FROM {comments} WHERE cid = %d", arg(2)));
+        if ($comment_exists) {
+          $items[] = array('path' => 'comment/delete', 'title' => t('delete comment'),
+            'callback' => 'comment_delete', 'access' => user_access('administer comments'), 'type' => MENU_CALLBACK);
+        }
+      }
+      else if (arg(1) == 'edit') {
+        $comment_exists = db_result(db_query("SELECT 1 FROM {comments} WHERE cid = %d", arg(2)));
+        if ($comment_exists) {
+          $items[] = array('path' => 'comment/edit', 'title' => t('edit comment'),
+            'callback' => 'comment_edit', 'access' => user_access('post comments'), 'type' => MENU_CALLBACK);
+        }
+      }
+      else if (arg(1) == 'reply') {
+        $node = node_load(arg(2));
+        if ($node->nid) {
+          $items[] = array('path' => 'comment/reply', 'title' => t('reply to comment'),
+            'callback' => 'comment_reply', 'access' => node_access('view', $node), 'type' => MENU_CALLBACK);
+        }
       }
     }
     if ((arg(0) == 'node') && is_numeric(arg(1)) && is_numeric(arg(2))) {