diff --git a/docs/MANUAL.rst b/docs/MANUAL.rst
index cf54985..6c29041 100644
--- a/docs/MANUAL.rst
+++ b/docs/MANUAL.rst
@@ -478,7 +478,8 @@ Another nametrans transpose example
 
 Put everything in a GMX. subfolder except for the boxes INBOX, Draft, and Sent which should keep the same name::
 
-     folderfilter = lambda folder: re.sub(r'^(?!INBOX$|Draft$|Sent$)',r'GMX.', folder)
+     nametrans = lambda folder: folder if folder in ['INBOX', 'Drafts', 'Sent'] \
+                               else re.sub(r'^', r'GMX.', folder)
 
 2 IMAP using name translations
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