...

src/calibre/ebooks/lit/writer.py

@@ -665,7 +665,7 @@ def _build_dchunks(self):
         name = directory[0].name
         for entry in directory:
             en = entry.name.encode('utf-8') if entry.name else entry.name
-            next = ''.join([decint(len(entry.name)), en,
+            next = ''.join([decint(len(en)), en,
                 decint(entry.section), decint(entry.offset),
                 decint(entry.size)])
             usedlen = dchunk.tell() + len(next) + (len(quickref) * 2) + 52