diff --git a/resources/sql/autopatches/20150804.ponder.answer.mailkey.1.sql b/resources/sql/autopatches/20150804.ponder.answer.mailkey.1.sql
new file mode 100644
--- /dev/null
+++ b/resources/sql/autopatches/20150804.ponder.answer.mailkey.1.sql
@@ -0,0 +1,2 @@
+ALTER TABLE {$NAMESPACE}_ponder.ponder_answer
+  ADD mailKey binary(20) NOT NULL;
diff --git a/resources/sql/autopatches/20150804.ponder.answer.mailkey.2.php b/resources/sql/autopatches/20150804.ponder.answer.mailkey.2.php
new file mode 100644
--- /dev/null
+++ b/resources/sql/autopatches/20150804.ponder.answer.mailkey.2.php
@@ -0,0 +1,18 @@
+<?php
+
+$table = new PonderAnswer();
+$conn_w = $table->establishConnection('w');
+$iterator = new LiskMigrationIterator($table);
+foreach ($iterator as $answer) {
+  $id = $answer->getID();
+
+  echo pht('Adding mail key for Answer %d...', $id);
+  echo "\n";
+
+  queryfx(
+    $conn_w,
+    'UPDATE %T SET mailKey = %s WHERE id = %d',
+    $table->getTableName(),
+    Filesystem::readRandomCharacters(20),
+    $id);
+}
diff --git a/src/applications/ponder/storage/PonderAnswer.php b/src/applications/ponder/storage/PonderAnswer.php
--- a/src/applications/ponder/storage/PonderAnswer.php
+++ b/src/applications/ponder/storage/PonderAnswer.php
@@ -18,6 +18,7 @@
 
   protected $content;
   protected $contentSource;
+  protected $mailKey;
 
   protected $voteCount;
   private $vote;
@@ -71,6 +72,7 @@
       self::CONFIG_COLUMN_SCHEMA => array(
         'voteCount' => 'sint32',
         'content' => 'text',
+        'mailKey' => 'bytes20',
 
         // T6203/NULLABILITY
         // This should always exist.
@@ -113,6 +115,13 @@
     return self::MARKUP_FIELD_CONTENT;
   }
 
+  public function save() {
+    if (!$this->getMailKey()) {
+      $this->setMailKey(Filesystem::readRandomCharacters(20));
+    }
+    return parent::save();
+  }
+
 
 /* -(  PhabricatorApplicationTransactionInterface  )------------------------- */