diff --git a/warden3/warden_client/warden_client.py b/warden3/warden_client/warden_client.py
index 297d2fad3b0c94a28f0b3c5413d2d59edc5eff09..6a807fca16533ec96adcd7156123f6d395b33eaa 100644
--- a/warden3/warden_client/warden_client.py
+++ b/warden3/warden_client/warden_client.py
@@ -8,7 +8,6 @@ import json, httplib, ssl, socket, logging, logging.handlers
 from urlparse import urlparse
 from urllib import urlencode
 from sys import stderr, exc_info
-from UserList import UserList
 from pprint import pformat
 from traceback import format_tb
 from os import path
@@ -69,8 +68,12 @@ class Error(Exception):
         self.cause = self.excval # compatibility with other exceptions
         if logger:
             getattr(logger, prio, "error")(str(self))
-            logger.info(self.info_str())
-            logger.debug(self.debug_str())
+            info = self.info_str()
+            if info:
+                logger.info(info)
+            debug = self.debug_str()
+            if debug:
+                logger.debug(debug)
 
 
     def __len__ (self):