diff --git a/src/calibre/ebooks/metadata/opf.py b/src/calibre/ebooks/metadata/opf.py
index e8075465a7..f5eb54bb6f 100644
--- a/src/calibre/ebooks/metadata/opf.py
+++ b/src/calibre/ebooks/metadata/opf.py
@@ -278,7 +278,7 @@ class OPF(MetaInformation):
     
     def get_comments(self):
         comments = self.soup.find('dc:description')
-        if comments:
+        if comments and comments.string:
             return self.ENTITY_PATTERN.sub(entity_to_unicode, comments.string).strip()
         return None
     
diff --git a/src/calibre/ebooks/metadata/toc.py b/src/calibre/ebooks/metadata/toc.py
index dc039a7f80..0069505f79 100644
--- a/src/calibre/ebooks/metadata/toc.py
+++ b/src/calibre/ebooks/metadata/toc.py
@@ -89,6 +89,7 @@ class TOC(list):
                     print 'Continuing anyway'
             else:
                 path = opfreader.manifest.item(toc.lower())
+                path = getattr(path, 'path', path)
                 if path and os.access(path, os.R_OK):
                     self.read_ncx_toc(path)
                     return