diff --git a/src/applications/diffusion/query/DiffusionCommitQuery.php b/src/applications/diffusion/query/DiffusionCommitQuery.php
--- a/src/applications/diffusion/query/DiffusionCommitQuery.php
+++ b/src/applications/diffusion/query/DiffusionCommitQuery.php
@@ -199,12 +199,19 @@
       $result = array();
       foreach ($commits as $commit) {
         $prefix = 'r'.$commit->getRepository()->getCallsign();
+        $prefix_id = 'r'.$commit->getRepository()->getID().':';
         $suffix = $commit->getCommitIdentifier();
 
         if ($commit->getRepository()->isSVN()) {
           if (isset($ids[$prefix.$suffix])) {
             $result[$prefix.$suffix][] = $commit;
           }
+          if (isset($ids[$prefix.':'.$suffix])) {
+            $result[$prefix.':'.$suffix][] = $commit;
+          }
+          if (isset($ids[$prefix_id.$suffix])) {
+            $result[$prefix_id.$suffix][] = $commit;
+          }
         } else {
           // This awkward construction is so we can link the commits up in O(N)
           // time instead of O(N^2).
@@ -213,6 +220,12 @@
             if (isset($ids[$prefix.$part])) {
               $result[$prefix.$part][] = $commit;
             }
+            if (isset($ids[$prefix.':'.$part])) {
+              $result[$prefix.':'.$part][] = $commit;
+            }
+            if (isset($ids[$prefix_id.$part])) {
+              $result[$prefix_id.$part][] = $commit;
+            }
             if (isset($ids[$part])) {
               $result[$part][] = $commit;
             }
@@ -327,8 +340,9 @@
       $bare = array();
       foreach ($this->identifiers as $identifier) {
         $matches = null;
-        preg_match('/^(?:r([A-Z]+))?(.*)$/', $identifier, $matches);
-        $repo = nonempty($matches[1], null);
+        // FIXME: Replace with CommitPHIDType::getCommitObjectNamePattern ??
+        preg_match('/^(?:r([A-Z]+:?|[0-9]+:))?(.*)$/', $identifier, $matches);
+        $repo = nonempty(rtrim($matches[1], ':'), null);
         $identifier = nonempty($matches[2], null);
 
         if ($repo === null) {
@@ -362,14 +376,28 @@
 
       if ($refs) {
         $callsigns = ipull($refs, 'callsign');
-        $repos = id(new PhabricatorRepositoryQuery())
+
+        $repos = array();
+        $repos_by_callsign = id(new PhabricatorRepositoryQuery())
           ->setViewer($this->getViewer())
           ->withCallsigns($callsigns)
           ->execute();
-        $repos = mpull($repos, null, 'getCallsign');
+        foreach ($repos_by_callsign as $obj) {
+          $repos[$obj->getCallsign()] = $obj;
+        }
+
+        $ids = array_filter($callsigns, 'is_numeric');
+        $repos_by_id = id(new PhabricatorRepositoryQuery())
+          ->setViewer($this->getViewer())
+          ->withIDs($ids)
+          ->execute();
+        foreach ($repos_by_id as $obj) {
+          $repos[$obj->getID()] = $obj;
+        }
 
         foreach ($refs as $key => $ref) {
           $repo = idx($repos, $ref['callsign']);
+
           if (!$repo) {
             continue;
           }
diff --git a/src/applications/diffusion/remarkup/DiffusionCommitRemarkupRule.php b/src/applications/diffusion/remarkup/DiffusionCommitRemarkupRule.php
--- a/src/applications/diffusion/remarkup/DiffusionCommitRemarkupRule.php
+++ b/src/applications/diffusion/remarkup/DiffusionCommitRemarkupRule.php
@@ -22,7 +22,6 @@
       ->withIdentifiers($ids);
 
     $query->execute();
-
     return $query->getIdentifierMap();
   }
 
diff --git a/src/applications/diffusion/remarkup/DiffusionRepositoryRemarkupRule.php b/src/applications/diffusion/remarkup/DiffusionRepositoryRemarkupRule.php
--- a/src/applications/diffusion/remarkup/DiffusionRepositoryRemarkupRule.php
+++ b/src/applications/diffusion/remarkup/DiffusionRepositoryRemarkupRule.php
@@ -8,18 +8,43 @@
   }
 
   protected function getObjectIDPattern() {
-    return '[A-Z]+';
+    return '[A-Z0-9]+';
   }
 
   protected function loadObjects(array $ids) {
     $viewer = $this->getEngine()->getConfig('viewer');
 
-    $repositories = id(new PhabricatorRepositoryQuery())
-      ->setViewer($viewer)
-      ->withCallsigns($ids)
-      ->execute();
+    $repo_ids = array(); $callsigns = array();
+    foreach ($ids as $id) {
+      if (is_numeric($id)) {
+        $repo_ids[] = $id;
+      } else {
+        $callsigns[] = $id;
+      }
+    }
 
-    return mpull($repositories, null, 'getCallsign');
+    $results = array();
+    if ($callsigns) {
+      $objects = id(new PhabricatorRepositoryQuery())
+        ->setViewer($viewer)
+        ->withCallsigns($callsigns)
+        ->execute();
+      foreach ($objects as $object) {
+        $results[$object->getCallsign()] = $object;
+      }
+    }
+
+    if ($repo_ids) {
+      $objects = id(new PhabricatorRepositoryQuery())
+        ->setViewer($viewer)
+        ->withIDs($repo_ids)
+        ->execute();
+      foreach ($objects as $object) {
+        $results[$object->getID()] = $object;
+      }
+    }
+
+    return $results;
   }
 
 }
diff --git a/src/applications/repository/phid/PhabricatorRepositoryCommitPHIDType.php b/src/applications/repository/phid/PhabricatorRepositoryCommitPHIDType.php
--- a/src/applications/repository/phid/PhabricatorRepositoryCommitPHIDType.php
+++ b/src/applications/repository/phid/PhabricatorRepositoryCommitPHIDType.php
@@ -54,9 +54,9 @@
     $min_qualified   = PhabricatorRepository::MINIMUM_QUALIFIED_HASH;
 
     return
-      'r[A-Z]+[1-9]\d*'.
+      'r([A-Z]+:?|[0-9]+:)[1-9]\d*'.
       '|'.
-      'r[A-Z]+[a-f0-9]{'.$min_qualified.',40}'.
+      'r([A-Z]+:?|[0-9]+:)[a-f0-9]{'.$min_qualified.',40}'.
       '|'.
       '[a-f0-9]{'.$min_unqualified.',40}';
   }
diff --git a/src/applications/repository/phid/PhabricatorRepositoryRepositoryPHIDType.php b/src/applications/repository/phid/PhabricatorRepositoryRepositoryPHIDType.php
--- a/src/applications/repository/phid/PhabricatorRepositoryRepositoryPHIDType.php
+++ b/src/applications/repository/phid/PhabricatorRepositoryRepositoryPHIDType.php
@@ -44,29 +44,41 @@
   }
 
   public function canLoadNamedObject($name) {
-    return preg_match('/^r[A-Z]+$/', $name);
+    return preg_match('/^r[A-Z0-9]+$/', $name);
   }
 
   public function loadNamedObjects(
     PhabricatorObjectQuery $query,
     array $names) {
 
-    $id_map = array();
+    $callsigns = array(); $ids = array();
     foreach ($names as $name) {
       $id = substr($name, 1);
-      $id_map[$id][] = $name;
+      if (is_numeric($id)) {
+        $ids[] = $id;
+      } else {
+        $callsigns[] = $id;
+      }
     }
 
-    $objects = id(new PhabricatorRepositoryQuery())
-      ->setViewer($query->getViewer())
-      ->withCallsigns(array_keys($id_map))
-      ->execute();
-
     $results = array();
-    foreach ($objects as $object) {
-      $callsign = $object->getCallsign();
-      foreach (idx($id_map, $callsign, array()) as $name) {
-        $results[$name] = $object;
+    if ($callsigns) {
+      $objects = id(new PhabricatorRepositoryQuery())
+        ->setViewer($query->getViewer())
+        ->withCallsigns($callsigns)
+        ->execute();
+      foreach ($objects as $object) {
+        $results[$object->getCallsign()] = $object;
+      }
+    }
+
+    if ($ids) {
+      $objects = id(new PhabricatorRepositoryQuery())
+        ->setViewer($query->getViewer())
+        ->withIDs($ids)
+        ->execute();
+      foreach ($objects as $object) {
+        $results[$object->getID()] = $object;
       }
     }