diff --git a/pykolab/imap_utf7.py b/pykolab/imap_utf7.py
--- a/pykolab/imap_utf7.py
+++ b/pykolab/imap_utf7.py
@@ -113,7 +113,7 @@
             b64_buffer.append(c)
         # No buffer initialized yet, should be an ASCII printable char
         else:
-            res.append(chr(c))
+            res.append(c)
 
     # Decode the remaining buffer if any
     if b64_buffer: