Index: src/applications/differential/conduit/ConduitAPI_differential_getrevisioncomments_Method.php
===================================================================
--- src/applications/differential/conduit/ConduitAPI_differential_getrevisioncomments_Method.php
+++ src/applications/differential/conduit/ConduitAPI_differential_getrevisioncomments_Method.php
@@ -53,6 +53,7 @@
     }
 
     foreach ($comments as $comment) {
+      // TODO: Sort this out in the ID -> PHID change.
       $revision_id = $comment->getRevisionID();
       $result = array(
         'revisionID'  => $revision_id,
Index: src/applications/differential/controller/DifferentialCommentPreviewController.php
===================================================================
--- src/applications/differential/controller/DifferentialCommentPreviewController.php
+++ src/applications/differential/controller/DifferentialCommentPreviewController.php
@@ -10,14 +10,20 @@
   }
 
   public function processRequest() {
-
     $request = $this->getRequest();
+    $viewer = $request->getUser();
+
+    $revision = id(new DifferentialRevisionQuery())
+      ->setViewer($viewer)
+      ->withIDs(array($this->id))
+      ->executeOne();
+    if (!$revision) {
+      return new Aphront404Response();
+    }
 
-    $author_phid = $request->getUser()->getPHID();
-
+    $author_phid = $viewer->getPHID();
     $action = $request->getStr('action');
 
-
     $comment = new DifferentialComment();
     $comment->setContent($request->getStr('content'));
     $comment->setAction($action);
@@ -51,6 +57,7 @@
     $view->setComment($comment);
     $view->setHandles($handles);
     $view->setMarkupEngine($engine);
+    $view->setRevision($revision);
     $view->setPreview(true);
     $view->setTargetDiff(null);
 
Index: src/applications/differential/controller/DifferentialRevisionViewController.php
===================================================================
--- src/applications/differential/controller/DifferentialRevisionViewController.php
+++ src/applications/differential/controller/DifferentialRevisionViewController.php
@@ -266,6 +266,7 @@
     $comment_view->setUser($user);
     $comment_view->setTargetDiff($target);
     $comment_view->setVersusDiffID($diff_vs);
+    $comment_view->setRevision($revision);
 
     if ($arc_project) {
       Javelin::initBehavior(
Index: src/applications/differential/view/DifferentialRevisionCommentListView.php
===================================================================
--- src/applications/differential/view/DifferentialRevisionCommentListView.php
+++ src/applications/differential/view/DifferentialRevisionCommentListView.php
@@ -9,6 +9,16 @@
   private $target;
   private $versusDiffID;
   private $id;
+  private $revision;
+
+  public function setRevision(DifferentialRevision $revision) {
+    $this->revision = $revision;
+    return $this;
+  }
+
+  public function getRevision() {
+    return $this->revision;
+  }
 
   public function setComments(array $comments) {
     assert_instances_of($comments, 'DifferentialComment');
@@ -86,6 +96,7 @@
       $view->setInlineComments(idx($inlines, $comment->getID(), array()));
       $view->setChangesets($this->changesets);
       $view->setTargetDiff($this->target);
+      $view->setRevision($this->getRevision());
       $view->setVersusDiffID($this->versusDiffID);
       if ($comment->getAction() == DifferentialAction::ACTION_SUMMARIZE) {
         $view->setAnchorName('summary');
Index: src/applications/differential/view/DifferentialRevisionCommentView.php
===================================================================
--- src/applications/differential/view/DifferentialRevisionCommentView.php
+++ src/applications/differential/view/DifferentialRevisionCommentView.php
@@ -11,6 +11,16 @@
   private $target;
   private $anchorName;
   private $versusDiffID;
+  private $revision;
+
+  public function setRevision(DifferentialRevision $revision) {
+    $this->revision = $revision;
+    return $this;
+  }
+
+  public function getRevision() {
+    return $this->revision;
+  }
 
   public function setComment($comment) {
     $this->comment = $comment;
@@ -134,7 +144,7 @@
           $diff_link = phutil_tag(
             'a',
             array(
-              'href' => '/D'.$comment->getRevisionID().'?id='.$diff_id,
+              'href' => '/D'.$this->getRevision()->getID().'?id='.$diff_id,
             ),
             'Diff #'.$diff_id);
           $actions[] = pht(
@@ -190,7 +200,7 @@
       $xaction_view->setEpoch($comment->getDateCreated());
       if ($this->anchorName) {
         $anchor_text =
-          'D'.$comment->getRevisionID().
+          'D'.$this->getRevision()->getID().
           '#'.preg_replace('/^comment-/', '', $this->anchorName);
 
         $xaction_view->setAnchor($this->anchorName, $anchor_text);
@@ -279,7 +289,7 @@
           $diff_id = $changeset->getDiffID();
           $item['where'] = '(On Diff #'.$diff_id.')';
           $item['href'] =
-            'D'.$this->comment->getRevisionID().
+            'D'.$this->getRevision()->getID().
             '?id='.$diff_id.
             '#inline-'.$inline->getID();
         }