diff --git a/src/calibre/startup.py b/src/calibre/startup.py
index b5741c1991..e384153993 100644
--- a/src/calibre/startup.py
+++ b/src/calibre/startup.py
@@ -16,7 +16,7 @@ __builtin__.__dict__['_'] = lambda s: s
 # immediately translated to the environment language
 __builtin__.__dict__['__'] = lambda s: s
 
-from calibre.constants import iswindows, preferred_encoding, plugins
+from calibre.constants import iswindows, preferred_encoding, plugins, isosx
 
 _run_once = False
 winutil = winutilerror = None
@@ -35,9 +35,17 @@ if not _run_once:
 
     ################################################################################
     # Convert command line arguments to unicode
+    enc = preferred_encoding
+    if isosx:
+        # Newer versions of OS X seem to use UTF-8
+        try:
+            [x.decode('utf-8') for x in sys.argv[1:]]
+            enc = 'utf-8'
+        except:
+            pass
     for i in range(1, len(sys.argv)):
         if not isinstance(sys.argv[i], unicode):
-            sys.argv[i] = sys.argv[i].decode(preferred_encoding, 'replace')
+            sys.argv[i] = sys.argv[i].decode(enc, 'replace')
 
     ################################################################################
     # Setup resources