Salam,
Long ago, under subject "some MULE inconsistencies [with patch]" I've
already sent half of that patches.  I now retry against 21.4.1 with
proper Cc: to xemacs-patches, ChangeLog entries, and more fixes.
If you need a patch to mule.texi over my patch from [20 Apr 2001],
just ask.
Probably more "@cindex"es are needed in mule.texi, I'm not sure.
2001-05-29  Alexey Mahotkin  <alexm(a)hsys.msk.ru>
	* coding.el: Tiny typo fixed
	* custom.texi: Documented keyboard shortcut.
	* mule.texi: Updated to match reality; tiny fixes.
===================================================================
RCS file: custom.texi,v
retrieving revision 1.1
diff -u -r1.1 custom.texi
--- custom.texi	2001/05/29 19:24:00	1.1
+++ custom.texi	2001/05/29 19:24:21
@@ -179,7 +179,8 @@
 @findex customize
 @cindex customization buffer
   A convenient way to find the user option variables that you want to
-change, and then change them, is with @kbd{M-x customize}.  This command
+change, and then change them, is with @kbd{M-x customize} (or use a
+keyboard shortcut, @kbd{C-h C}.  This command
 creates a @dfn{customization buffer} with which you can browse through
 the Emacs user options in a logically organized structure, then edit and
 set their values.  You can also use the customization buffer to save
@@ -203,7 +204,7 @@
 @dfn{groups} to help you find them.  Groups are collected into bigger
 groups, all the way up to a master group called @code{Emacs}.
 
-  @kbd{M-x customize} creates a customization buffer that shows the
+  @kbd{M-x customize} (or @kbd{C-h C} creates a customization buffer that shows the
 top-level @code{Emacs} group and the second-level groups immediately
 under it.  It looks like this, in part:
 
===================================================================
RCS file: mule.texi,v
retrieving revision 1.1
diff -u -r1.1 mule.texi
--- mule.texi	2001/05/29 18:13:14	1.1
+++ mule.texi	2001/05/29 19:17:36
@@ -13,8 +13,9 @@
 @cindex IPA
 @cindex Japanese
 @cindex Korean
+@cindex Cyrillic
 @cindex Russian
-  If you compile XEmacs with mule option, it supports a wide variety of
+  If you compile XEmacs with Mule option, it supports a wide variety of
 world scripts, including Latin script, as well as Arabic script,
 Simplified Chinese script (for mainland of China), Traditional Chinese
 script (for Taiwan and Hong-Kong), Greek script, Hebrew script, IPA
@@ -70,7 +71,7 @@
 @cindex language environments
 
   All supported character sets are supported in XEmacs buffers if it is
-compile with mule; there is no need to select a particular language in
+compiled with Mule; there is no need to select a particular language in
 order to display its characters in an XEmacs buffer.  However, it is
 important to select a @dfn{language environment} in order to set various
 defaults.  The language environment really represents a choice of
@@ -89,8 +90,10 @@
 the XEmacs session.  The supported language environments include:
 
 @quotation
-Chinese-BIG5, Chinese-CNS, Chinese-GB, Cyrillic-ISO, English, Ethiopic,
-Greek, Japanese, Korean, Latin-1, Latin-2, Latin-3, Latin-4, Latin-5.
+ASCII, Chinese-BIG5, Chinese-GB, Croatian, Cyrillic-ALT, Cyrillic-ISO, 
+Cyrillic-KOI8, Cyrillic-Win, Czech, English, Ethiopic, French, German,
+Greek, Hebrew, IPA, Japanese, Korean, Latin-1, Latin-2, Latin-3, Latin-4,
+Latin-5, Norwegian, Polish, Romanian, Slovenian, Thai-XTIS, Vietnamese.
 @end quotation
 
   Some operating systems let you specify the language you are using by
@@ -282,11 +285,15 @@
 
 @item M-x list-coding-systems
 Display a list of all the supported coding systems.
+
+@item C-u M-x list-coding-systems
+Display comprehensive list of specific details of all supported coding
+systems.
 @end table
 
-@kindex C-h C
+@kindex C-x @key{RET} C
 @findex describe-coding-system
-  The command @kbd{C-h C} (@code{describe-coding-system}) displays
+  The command @kbd{C-x RET C} (@code{describe-coding-system}) displays
 information about particular coding systems.  You can specify a coding
 system name as argument; alternatively, with an empty argument, it
 describes the coding systems currently selected for various purposes,
@@ -435,7 +442,8 @@
 command.
 
 @item C-x @key{RET} k @var{coding} @key{RET}
-Use coding system @var{coding} for keyboard input.
+Use coding system @var{coding} for keyboard input.  (This feature is
+non-functional and is temporarily disabled.)
 
 @item C-x @key{RET} t @var{coding} @key{RET}
 Use coding system @var{coding} for terminal output.
@@ -517,6 +525,8 @@
 the sequences that are translated are typically sequences of ASCII
 printing characters.  Coding systems typically translate sequences of
 non-graphic characters.
+
+(This feature is non-functional and is temporarily disabled.)
 
 @kindex C-x RET p
 @findex set-buffer-process-coding-system
===================================================================
RCS file: coding.el,v
retrieving revision 1.1
diff -u -r1.1 coding.el
--- coding.el	2001/05/29 19:31:22	1.1
+++ coding.el	2001/05/29 18:53:38
@@ -50,7 +50,7 @@
 TARGET-TYPE specifies which of them to modify.
 If it is `file', it affects `file-coding-system-alist' (which see).
 If it is `process', it affects `process-coding-system-alist' (which see).
-If it is `network', it affects `network-codign-system-alist' (which see).
+If it is `network', it affects `network-coding-system-alist' (which see).
 
 REGEXP is a regular expression matching a target of I/O operation.
 The target is a file name if TARGET-TYPE is `file', a program name if