document all the valid encoding values
diff --git a/Doc/lib/libmimetools.tex b/Doc/lib/libmimetools.tex
index ba12d53..28efec0 100644
--- a/Doc/lib/libmimetools.tex
+++ b/Doc/lib/libmimetools.tex
@@ -29,7 +29,10 @@
Read data encoded using the allowed MIME \var{encoding} from open file
object \var{input} and write the decoded data to open file object
\var{output}. Valid values for \var{encoding} include
-\code{'base64'}, \code{'quoted-printable'} and \code{'uuencode'}.
+\code{'base64'}, \code{'quoted-printable'}, \code{'uuencode'},
+\code{'x-uuencode'}, \code{'uue'}, \code{'x-uue'}, \code{'7bit'}, and
+\code{'8bit'}. Decoding messages encoded in \code{'7bit'} or \code{'8bit'}
+has no effect. The input is simply copied to the output.
\end{funcdesc}
\begin{funcdesc}{encode}{input, output, encoding}