diff --git a/lacre/core.py b/lacre/core.py
index 1239eb3..3c6a121 100644
--- a/lacre/core.py
+++ b/lacre/core.py
@@ -133,8 +133,8 @@ def _gpg_encrypt_to_bytes(message: EmailMessage, keys, recipients, encrypt_f, lm
     msg_copy = _gpg_encrypt_copy(message, keys, recipients, encrypt_f, lmessage)
     try:
         return msg_copy.as_bytes(policy=SMTPUTF8)
-    except IndexError:
-        raise MailSerialisationException()
+    except IndexError as ie:
+        raise MailSerialisationException(ie)
 
 
 def _gpg_encrypt_to_str(message: EmailMessage, keys, recipients, encrypt_f) -> str:
diff --git a/lacre/daemon.py b/lacre/daemon.py
index 137b890..2d4ffe3 100644
--- a/lacre/daemon.py
+++ b/lacre/daemon.py
@@ -54,7 +54,7 @@ class MailEncryptionProxy:
                         # If the message can't be encrypted or serialised to a
                         # stream of bytes, deliver original payload in
                         # cleartext.
-                        LOG.error('Unable to encrypt message, delivering in cleartext: %s', e)
+                        LOG.exception('Unable to encrypt message, delivering in cleartext: %s')
                         self._send_unencrypted(operation, envelope, send)
 
             except xport.TransientFailure: