diff --git a/src/calibre/ebooks/lit/reader.py b/src/calibre/ebooks/lit/reader.py
index 1668d2bc5c..87d0a29088 100644
--- a/src/calibre/ebooks/lit/reader.py
+++ b/src/calibre/ebooks/lit/reader.py
@@ -643,11 +643,14 @@ class LitReader(object):
             self.drmlevel = 1
         else:
             return
-        msdes.deskey(self._calculate_deskey(), msdes.DE1)
-        bookkey = msdes.des(self.get_file('/DRMStorage/DRMSealed'))
-        if bookkey[0] != '\000':
-            raise LitError('Unable to decrypt title key!')
-        self.bookkey = bookkey[1:9]
+        if self.drmlevel < 5:
+            msdes.deskey(self._calculate_deskey(), msdes.DE1)
+            bookkey = msdes.des(self.get_file('/DRMStorage/DRMSealed'))
+            if bookkey[0] != '\000':
+                raise LitError('Unable to decrypt title key!')
+            self.bookkey = bookkey[1:9]
+        else:
+            raise LitError('Cannot extract content from a DRM protected ebook')
 
     def _calculate_deskey(self):
         hashfiles = ['/meta', '/DRMStorage/DRMSource']
@@ -710,8 +713,6 @@ class LitReader(object):
         return content
 
     def _decrypt(self, content):
-        if self.drmlevel == 5:
-            raise LitError('Cannot extract content from a DRM protected ebook')
         msdes.deskey(self.bookkey, msdes.DE1)
         return msdes.des(content)
 
diff --git a/src/calibre/ebooks/metadata/opf.py b/src/calibre/ebooks/metadata/opf.py
index f5eb54bb6f..dcda78258a 100644
--- a/src/calibre/ebooks/metadata/opf.py
+++ b/src/calibre/ebooks/metadata/opf.py
@@ -1,10 +1,11 @@
-import cStringIO
 __license__   = 'GPL v3'
 __copyright__ = '2008, Kovid Goyal <kovid at kovidgoyal.net>'
-import uuid
 '''Read/Write metadata from Open Packaging Format (.opf) files.'''
 
 import sys, re, os, glob
+import cStringIO
+import uuid
+from urllib import unquote, quote
 
 from calibre import __appname__
 from calibre.ebooks.metadata import MetaInformation
@@ -25,7 +26,10 @@ class ManifestItem(Resource):
     @staticmethod
     def from_opf_manifest_item(item, basedir):
         if item.has_key('href'):
-            res = ManifestItem(item['href'], basedir=basedir, is_path=False)
+            href = item['href']
+            if unquote(href) == href:
+                href = quote(href)
+            res = ManifestItem(href, basedir=basedir, is_path=False)
             mt = item.get('media-type', '').strip()
             if mt:
                 res.mime_type = mt