diff --git a/src/applications/metamta/management/PhabricatorMailManagementShowInboundWorkflow.php b/src/applications/metamta/management/PhabricatorMailManagementShowInboundWorkflow.php
index 5226bd2dc2..ea2bf197dd 100644
--- a/src/applications/metamta/management/PhabricatorMailManagementShowInboundWorkflow.php
+++ b/src/applications/metamta/management/PhabricatorMailManagementShowInboundWorkflow.php
@@ -1,103 +1,106 @@
 <?php
 
 final class PhabricatorMailManagementShowInboundWorkflow
   extends PhabricatorSearchManagementWorkflow {
 
   protected function didConstruct() {
     $this
       ->setName('show-inbound')
       ->setSynopsis('Show diagnostic details about inbound mail.')
       ->setExamples(
         "**show-inbound** --id 1 --id 2")
       ->setArguments(
         array(
           array(
             'name'    => 'id',
             'param'   => 'id',
             'help'    => 'Show details about inbound mail with given ID.',
             'repeat'  => true,
           ),
         ));
   }
 
   public function execute(PhutilArgumentParser $args) {
     $console = PhutilConsole::getConsole();
 
     $ids = $args->getArg('id');
     if (!$ids) {
       throw new PhutilArgumentUsageException(
         "Use the '--id' flag to specify one or more messages to show.");
     }
 
     $messages = id(new PhabricatorMetaMTAReceivedMail())->loadAllWhere(
       'id IN (%Ld)',
       $ids);
 
     if ($ids) {
       $ids = array_fuse($ids);
       $missing = array_diff_key($ids, $messages);
       if ($missing) {
         throw new PhutilArgumentUsageException(
           "Some specified messages do not exist: ".
           implode(', ', array_keys($missing)));
       }
     }
 
     $last_key = last_key($messages);
     foreach ($messages as $message_key => $message) {
       $info = array();
 
       $info[] = pht('PROPERTIES');
       $info[] = pht('ID: %d', $message->getID());
       $info[] = pht('Status: %s', $message->getStatus());
       $info[] = pht('Related PHID: %s', $message->getRelatedPHID());
       $info[] = pht('Author PHID: %s', $message->getAuthorPHID());
       $info[] = pht('Message ID Hash: %s', $message->getMessageIDHash());
 
       if ($message->getMessage()) {
         $info[] = null;
         $info[] = pht('MESSAGE');
         $info[] = $message->getMessage();
       }
 
       $info[] = null;
       $info[] = pht('HEADERS');
       foreach ($message->getHeaders() as $key => $value) {
+        if (is_array($value)) {
+          $value = implode("\n", $value);
+        }
         $info[] = pht('%s: %s', $key, $value);
       }
 
       $bodies = $message->getBodies();
 
       $last_body = last_key($bodies);
 
       $info[] = null;
       $info[] = pht('BODIES');
       foreach ($bodies as $key => $value) {
         $info[] = pht('Body "%s"', $key);
         $info[] = $value;
         if ($key != $last_body) {
           $info[] = null;
         }
       }
 
       $attachments = $message->getAttachments();
 
       $info[] = null;
       $info[] = pht('ATTACHMENTS');
       if (!$attachments) {
         $info[] = pht('No attachments.');
       } else {
         foreach ($attachments as $attachment) {
           $info[] = pht('File PHID: %s', $attachment);
         }
       }
 
       $console->writeOut("%s\n", implode("\n", $info));
 
       if ($message_key != $last_key) {
         $console->writeOut("\n%s\n\n", str_repeat('-', 80));
       }
     }
   }
 
 }
diff --git a/src/applications/metamta/receiver/PhabricatorObjectMailReceiver.php b/src/applications/metamta/receiver/PhabricatorObjectMailReceiver.php
index 9202e710f5..8c88e4e1f5 100644
--- a/src/applications/metamta/receiver/PhabricatorObjectMailReceiver.php
+++ b/src/applications/metamta/receiver/PhabricatorObjectMailReceiver.php
@@ -1,179 +1,181 @@
 <?php
 
 abstract class PhabricatorObjectMailReceiver extends PhabricatorMailReceiver {
 
   /**
    * Return a regular expression fragment which matches the name of an
    * object which can receive mail. For example, Differential uses:
    *
    *  D[1-9]\d*
    *
    * ...to match `D123`, etc., identifying Differential Revisions.
    *
    * @return string Regular expression fragment.
    */
   abstract protected function getObjectPattern();
 
 
   /**
    * Load the object receiving mail, based on an identifying pattern. Normally
    * this pattern is some sort of object ID.
    *
    * @param   string          A string matched by @{method:getObjectPattern}
    *                          fragment.
    * @param   PhabricatorUser The viewing user.
    * @return  void
    */
   abstract protected function loadObject($pattern, PhabricatorUser $viewer);
 
 
   final protected function processReceivedMail(
     PhabricatorMetaMTAReceivedMail $mail,
     PhabricatorUser $sender) {
 
     $object = $this->loadObjectFromMail($mail, $sender);
     $mail->setRelatedPHID($object->getPHID());
 
     $this->processReceivedObjectMail($mail, $object, $sender);
 
     return $this;
   }
 
   abstract protected function processReceivedObjectMail(
     PhabricatorMetaMTAReceivedMail $mail,
     PhabricatorLiskDAO $object,
     PhabricatorUser $sender);
 
   public function loadMailReceiverObject($pattern, PhabricatorUser $viewer) {
     return $this->loadObject($pattern, $viewer);
   }
 
   public function validateSender(
     PhabricatorMetaMTAReceivedMail $mail,
     PhabricatorUser $sender) {
 
     parent::validateSender($mail, $sender);
 
     $parts = $this->matchObjectAddressInMail($mail);
 
     try {
       $object = $this->loadObjectFromMail($mail, $sender);
     } catch (PhabricatorPolicyException $policy_exception) {
       throw new PhabricatorMetaMTAReceivedMailProcessingException(
         MetaMTAReceivedMailStatus::STATUS_POLICY_PROBLEM,
         pht(
           "This mail is addressed to an object you are not permitted ".
           "to see: %s",
           $policy_exception->getMessage()));
     }
 
     if (!$object) {
       throw new PhabricatorMetaMTAReceivedMailProcessingException(
         MetaMTAReceivedMailStatus::STATUS_NO_SUCH_OBJECT,
         pht(
           "This mail is addressed to an object ('%s'), but that object ".
           "does not exist.",
           $parts['pattern']));
     }
 
     $sender_identifier = $parts['sender'];
 
     if ($sender_identifier === 'public') {
       if (!PhabricatorEnv::getEnvConfig('metamta.public-replies')) {
         throw new PhabricatorMetaMTAReceivedMailProcessingException(
           MetaMTAReceivedMailStatus::STATUS_NO_PUBLIC_MAIL,
           pht(
             "This mail is addressed to an object's public address, but ".
             "public replies are not enabled (`metamta.public-replies`)."));
       }
       $check_phid = $object->getPHID();
     } else {
       if ($sender_identifier != $sender->getID()) {
         throw new PhabricatorMetaMTAReceivedMailProcessingException(
           MetaMTAReceivedMailStatus::STATUS_USER_MISMATCH,
           pht(
             "This mail is addressed to an object's private address, but ".
             "the sending user and the private address owner are not the ".
             "same user."));
       }
       $check_phid = $sender->getPHID();
     }
 
     $expect_hash = self::computeMailHash($object->getMailKey(), $check_phid);
 
     if ($expect_hash != $parts['hash']) {
       throw new PhabricatorMetaMTAReceivedMailProcessingException(
         MetaMTAReceivedMailStatus::STATUS_HASH_MISMATCH,
         pht(
           "The hash in this object's address does not match the expected ".
           "value."));
     }
   }
 
 
   final public function canAcceptMail(PhabricatorMetaMTAReceivedMail $mail) {
     if ($this->matchObjectAddressInMail($mail)) {
       return true;
     }
 
     return false;
   }
 
   private function matchObjectAddressInMail(
     PhabricatorMetaMTAReceivedMail $mail) {
 
     foreach ($mail->getToAddresses() as $address) {
       $parts = $this->matchObjectAddress($address);
       if ($parts) {
         return $parts;
       }
     }
 
     return null;
   }
 
   private function matchObjectAddress($address) {
     $regexp = $this->getAddressRegexp();
 
     $address = self::stripMailboxPrefix($address);
     $local = id(new PhutilEmailAddress($address))->getLocalPart();
 
     $matches = null;
     if (!preg_match($regexp, $local, $matches)) {
       return false;
     }
 
     return $matches;
   }
 
   private function getAddressRegexp() {
     $pattern = $this->getObjectPattern();
 
     $regexp =
       '(^'.
         '(?P<pattern>'.$pattern.')'.
         '\\+'.
         '(?P<sender>\w+)'.
         '\\+'.
         '(?P<hash>[a-f0-9]{16})'.
-      '$)U';
+      '$)Ui';
 
     return $regexp;
   }
 
   private function loadObjectFromMail(
     PhabricatorMetaMTAReceivedMail $mail,
     PhabricatorUser $sender) {
     $parts = $this->matchObjectAddressInMail($mail);
 
-    return $this->loadObject($parts['pattern'], $sender);
+    return $this->loadObject(
+      phutil_utf8_strtoupper($parts['pattern']),
+      $sender);
   }
 
   public static function computeMailHash($mail_key, $phid) {
     $global_mail_key = PhabricatorEnv::getEnvConfig('phabricator.mail-key');
 
     $hash = PhabricatorHash::digest($mail_key.$global_mail_key.$phid);
     return substr($hash, 0, 16);
   }
 
 }