diff --git a/pykolab/imap_utf7.py b/pykolab/imap_utf7.py
--- a/pykolab/imap_utf7.py
+++ b/pykolab/imap_utf7.py
@@ -112,6 +112,8 @@
         elif b64_buffer:
             b64_buffer.append(c)
         # No buffer initialized yet, should be an ASCII printable char
+        elif isinstance(c, int):
+            res.append(chr(c))
         else:
             res.append(c)