diff --git a/src/calibre/devices/apple/driver.py b/src/calibre/devices/apple/driver.py
index ec116ec91b..7e9ca43ce2 100644
--- a/src/calibre/devices/apple/driver.py
+++ b/src/calibre/devices/apple/driver.py
@@ -682,8 +682,13 @@ class ITUNES(DevicePlugin):
         '''
         Fetch the size of a book stored on the device
         '''
+        if DEBUG:
+            self.log.info("ITUNES._get_device_book_size(): looking for title: '%s' author: %s" % (title,author))
+
         device_books = self._get_device_books()
         for d_book in device_books:
+            if DEBUG:
+                self.log.info(" evaluating title: '%s' author: '%s'" % (d_book.name(), d_book.artist()))
             if d_book.name() == title and d_book.artist() == author:
                 return d_book.size()
         else:
diff --git a/src/calibre/devices/errors.py b/src/calibre/devices/errors.py
index 8191b15db6..7464d6635e 100644
--- a/src/calibre/devices/errors.py
+++ b/src/calibre/devices/errors.py
@@ -27,7 +27,7 @@ class DeviceError(ProtocolError):
 
 class UserFeedback(DeviceError):
    INFO = 0
-   WARN = 1
+   WARN = WARNING = 1
    ERROR = 2
 
    def __init__(self, msg, details, level):