diff --git a/runtime/syntax/scheme.vim b/runtime/syntax/scheme.vim
index d3de35b..1d4f55d 100644
--- a/runtime/syntax/scheme.vim
+++ b/runtime/syntax/scheme.vim
@@ -1,11 +1,14 @@
 " Vim syntax file
 " Language:	Scheme (R5RS)
-" Maintainer:	Dirk van Deun <dirk@igwe.vub.ac.be>
-" Last Change:	April 30, 1998
+" Last Change:	July 14, 2004
+" Maintainer:	Sergey Khorev <iamphet@nm.ru>
+" Original author:	Dirk van Deun <dirk@igwe.vub.ac.be>
 
 " This script incorrectly recognizes some junk input as numerals:
 " parsing the complete system of Scheme numerals using the pattern
 " language is practically impossible: I did a lax approximation.
+ 
+" MzScheme extensions can be activated with setting is_mzscheme variable
 
 " Suggestions and bug reports are solicited by the author.
 
@@ -23,12 +26,12 @@
 
 " Fascist highlighting: everything that doesn't fit the rules is an error...
 
-syn match	schemeError	oneline    ![^ \t()";]*!
+syn match	schemeError	oneline    ![^ \t()\[\]";]*!
 syn match	schemeError	oneline    ")"
 
 " Quoted and backquoted stuff
 
-syn region schemeQuoted matchgroup=Delimiter start="['`]" end=![ \t()";]!me=e-1 contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
+syn region schemeQuoted matchgroup=Delimiter start="['`]" end=![ \t()\[\]";]!me=e-1 contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
 
 syn region schemeQuoted matchgroup=Delimiter start="['`](" matchgroup=Delimiter end=")" contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
 syn region schemeQuoted matchgroup=Delimiter start="['`]#(" matchgroup=Delimiter end=")" contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
@@ -36,15 +39,26 @@
 syn region schemeStrucRestricted matchgroup=Delimiter start="(" matchgroup=Delimiter end=")" contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
 syn region schemeStrucRestricted matchgroup=Delimiter start="#(" matchgroup=Delimiter end=")" contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
 
-syn region schemeUnquote matchgroup=Delimiter start="," end=![ \t()";]!me=e-1 contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
-syn region schemeUnquote matchgroup=Delimiter start=",@" end=![ \t()";]!me=e-1 contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
+" Popular Scheme extension:
+" using [] as well as ()
+syn region schemeStrucRestricted matchgroup=Delimiter start="\[" matchgroup=Delimiter end="\]" contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
+syn region schemeStrucRestricted matchgroup=Delimiter start="#\[" matchgroup=Delimiter end="\]" contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
 
-syn region schemeUnquote matchgroup=Delimiter start=",(" end=")" contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
-syn region schemeUnquote matchgroup=Delimiter start=",@(" end=")" contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
+syn region schemeUnquote matchgroup=Delimiter start="," end=![ \t\[\]()";]!me=e-1 contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
+syn region schemeUnquote matchgroup=Delimiter start=",@" end=![ \t\[\]()";]!me=e-1 contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
+
+syn region schemeUnquote matchgroup=Delimiter start=",(" end=")" contains=ALL
+syn region schemeUnquote matchgroup=Delimiter start=",@(" end=")" contains=ALL
 
 syn region schemeUnquote matchgroup=Delimiter start=",#(" end=")" contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
 syn region schemeUnquote matchgroup=Delimiter start=",@#(" end=")" contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
 
+syn region schemeUnquote matchgroup=Delimiter start=",\[" end="\]" contains=ALL
+syn region schemeUnquote matchgroup=Delimiter start=",@\[" end="\]" contains=ALL
+
+syn region schemeUnquote matchgroup=Delimiter start=",#\[" end="\]" contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
+syn region schemeUnquote matchgroup=Delimiter start=",@#\[" end="\]" contains=ALLBUT,schemeStruc,schemeSyntax,schemeFunc
+
 " R5RS Scheme Functions and Syntax:
 
 if version < 600
@@ -96,63 +110,126 @@
 syn keyword schemeFunc scheme-report-environment null-environment
 syn keyword schemeFunc interaction-environment
 
-" Writing out the complete description of Scheme numerals without
-" using variables is a day's work for a trained secretary...
-" This is a useful lax approximation:
-
-syn match	schemeNumber	oneline    "[-#+0-9.][-#+/0-9a-f@i.boxesfdl]*"
-syn match	schemeError	oneline    ![-#+0-9.][-#+/0-9a-f@i.boxesfdl]*[^-#+/0-9a-f@i.boxesfdl \t()";][^ \t()";]*!
-
-syn match	schemeOther	oneline    ![+-][ \t()";]!me=e-1
-syn match	schemeOther	oneline    ![+-]$!
 " ... so that a single + or -, inside a quoted context, would not be
 " interpreted as a number (outside such contexts, it's a schemeFunc)
 
-syn match	schemeDelimiter	oneline    !\.[ \t()";]!me=e-1
+syn match	schemeDelimiter	oneline    !\.[ \t\[\]()";]!me=e-1
 syn match	schemeDelimiter	oneline    !\.$!
 " ... and a single dot is not a number but a delimiter
 
-" Simple literals:
-
-syn match	schemeBoolean	oneline    "#[tf]"
-syn match	schemeError	oneline    !#[tf][^ \t()";]\+!
-
-syn match	schemeChar	oneline    "#\\"
-syn match	schemeChar	oneline    "#\\."
-syn match       schemeError	oneline    !#\\.[^ \t()";]\+!
-syn match	schemeChar	oneline    "#\\space"
-syn match	schemeError	oneline    !#\\space[^ \t()";]\+!
-syn match	schemeChar	oneline    "#\\newline"
-syn match	schemeError	oneline    !#\\newline[^ \t()";]\+!
-
 " This keeps all other stuff unhighlighted, except *stuff* and <stuff>:
 
-syn match	schemeOther	oneline    ,[a-z!$%&*/:<=>?^_~][-a-z!$%&*/:<=>?^_~0-9+.@]*,
-syn match	schemeError	oneline    ,[a-z!$%&*/:<=>?^_~][-a-z!$%&*/:<=>?^_~0-9+.@]*[^-a-z!$%&*/:<=>?^_~0-9+.@ \t()";]\+[^ \t()";]*,
+syn match	schemeOther	oneline    ,[a-z!$%&*/:<=>?^_~+@#%-][-a-z!$%&*/:<=>?^_~0-9+.@#%]*,
+syn match	schemeError	oneline    ,[a-z!$%&*/:<=>?^_~+@#%-][-a-z!$%&*/:<=>?^_~0-9+.@#%]*[^-a-z!$%&*/:<=>?^_~0-9+.@ \t\[\]()";]\+[^ \t\[\]()";]*,
 
 syn match	schemeOther	oneline    "\.\.\."
-syn match	schemeError	oneline    !\.\.\.[^ \t()";]\+!
+syn match	schemeError	oneline    !\.\.\.[^ \t\[\]()";]\+!
 " ... a special identifier
 
-syn match	schemeConstant	oneline    ,\*[-a-z!$%&*/:<=>?^_~0-9+.@]*\*[ \t()";],me=e-1
+syn match	schemeConstant	oneline    ,\*[-a-z!$%&*/:<=>?^_~0-9+.@]*\*[ \t\[\]()";],me=e-1
 syn match	schemeConstant	oneline    ,\*[-a-z!$%&*/:<=>?^_~0-9+.@]*\*$,
-syn match	schemeError	oneline    ,\*[-a-z!$%&*/:<=>?^_~0-9+.@]*\*[^-a-z!$%&*/:<=>?^_~0-9+.@ \t()";]\+[^ \t()";]*,
+syn match	schemeError	oneline    ,\*[-a-z!$%&*/:<=>?^_~0-9+.@]*\*[^-a-z!$%&*/:<=>?^_~0-9+.@ \t\[\]()";]\+[^ \t\[\]()";]*,
 
-syn match	schemeConstant	oneline    ,<[-a-z!$%&*/:<=>?^_~0-9+.@]*>[ \t()";],me=e-1
+syn match	schemeConstant	oneline    ,<[-a-z!$%&*/:<=>?^_~0-9+.@]*>[ \t\[\]()";],me=e-1
 syn match	schemeConstant	oneline    ,<[-a-z!$%&*/:<=>?^_~0-9+.@]*>$,
-syn match	schemeError	oneline    ,<[-a-z!$%&*/:<=>?^_~0-9+.@]*>[^-a-z!$%&*/:<=>?^_~0-9+.@ \t()";]\+[^ \t()";]*,
+syn match	schemeError	oneline    ,<[-a-z!$%&*/:<=>?^_~0-9+.@]*>[^-a-z!$%&*/:<=>?^_~0-9+.@ \t\[\]()";]\+[^ \t\[\]()";]*,
 
 " Non-quoted lists, and strings:
 
 syn region schemeStruc matchgroup=Delimiter start="(" matchgroup=Delimiter end=")" contains=ALL
 syn region schemeStruc matchgroup=Delimiter start="#(" matchgroup=Delimiter end=")" contains=ALL
 
+syn region schemeStruc matchgroup=Delimiter start="\[" matchgroup=Delimiter end="\]" contains=ALL
+syn region schemeStruc matchgroup=Delimiter start="#\[" matchgroup=Delimiter end="\]" contains=ALL
+
+" Simple literals:
 syn region	schemeString	start=+"+  skip=+\\[\\"]+ end=+"+
 
 " Comments:
 
 syn match	schemeComment	";.*$"
 
+
+" Writing out the complete description of Scheme numerals without
+" using variables is a day's work for a trained secretary...
+
+syn match	schemeOther	oneline    ![+-][ \t\[\]()";]!me=e-1
+syn match	schemeOther	oneline    ![+-]$!
+"
+" This is a useful lax approximation:
+syn match	schemeNumber	oneline    "[-#+0-9.][-#+/0-9a-f@i.boxesfdl]*"
+syn match	schemeError	oneline    ![-#+0-9.][-#+/0-9a-f@i.boxesfdl]*[^-#+/0-9a-f@i.boxesfdl \t\[\]()";][^ \t\[\]()";]*!
+
+syn match	schemeBoolean	oneline    "#[tf]"
+syn match	schemeError	oneline    !#[tf][^ \t\[\]()";]\+!
+
+syn match	schemeChar	oneline    "#\\"
+syn match	schemeChar	oneline    "#\\."
+syn match       schemeError	oneline    !#\\.[^ \t\[\]()";]\+!
+syn match	schemeChar	oneline    "#\\space"
+syn match	schemeError	oneline    !#\\space[^ \t\[\]()";]\+!
+syn match	schemeChar	oneline    "#\\newline"
+syn match	schemeError	oneline    !#\\newline[^ \t\[\]()";]\+!
+
+if exists("b:is_mzscheme") || exists("is_mzscheme")
+    " MzScheme extensions added by Sergey Khorev
+    " multiline comment
+    syntax region schemeMultilineComment start=/#|/ end=/|#/
+    " #%xxx are the special MzScheme identifiers
+    syn match schemeOther oneline    "#%[-a-z!$%&*/:<=>?^_~0-9+.@#%]\+"
+    " anything limited by |'s is identifier
+    syn match schemeOther oneline    "|[^|]\+|"
+
+    syn match	schemeChar	oneline    "#\\return"
+
+    " Modules require stmt
+    syn keyword schemeExtSyntax module require dynamic-require lib prefix all-except prefix-all-except rename
+    " modules provide stmt
+    syn keyword schemeExtSyntax provide struct all-from all-from-except all-defined all-defined-except
+    " Other from MzScheme
+    syn keyword schemeExtSyntax with-handlers when unless instantiate define-struct case-lambda syntax-case
+    syn keyword schemeExtSyntax free-identifier=? bound-identifier=? module-identifier=? syntax-object->datum
+    syn keyword schemeExtSyntax datum->syntax-object
+    syn keyword schemeExtSyntax let-values let*-values letrec-values set!-values fluid-let parameterize begin0
+    syn keyword schemeExtSyntax error raise opt-lambda define-values unit unit/sig define-signature 
+    syn keyword schemeExtSyntax invoke-unit/sig define-values/invoke-unit/sig compound-unit/sig import export
+    syn keyword schemeExtSyntax link syntax quasisyntax unsyntax with-syntax
+    hi def link schemeExtSyntax Type
+
+    syn keyword schemeExtFunc format system-type current-extension-compiler current-extension-linker
+    syn keyword schemeExtFunc use-standard-linker use-standard-compiler
+    syn keyword schemeExtFunc find-executable-path append-object-suffix append-extension-suffix
+    syn keyword schemeExtFunc current-library-collection-paths current-extension-compiler-flags make-parameter
+    syn keyword schemeExtFunc current-directory build-path normalize-path current-extension-linker-flags
+    syn keyword schemeExtFunc file-exists? directory-exists? delete-directory/files delete-directory delete-file
+    syn keyword schemeExtFunc system compile-file system-library-subpath getenv putenv current-standard-link-libraries
+    syn keyword schemeExtFunc remove* file-size find-files fold-files directory-list shell-execute split-path
+    syn keyword schemeExtFunc current-error-port process/ports process printf fprintf open-input-string open-output-string
+    syn keyword schemeExtFunc get-output-string
+    " exceptions
+    syn keyword schemeExtFunc exn exn:application:arity exn:application:continuation exn:application:fprintf:mismatch
+    syn keyword schemeExtFunc exn:application:mismatch exn:application:type exn:application:mismatch exn:break exn:i/o:filesystem exn:i/o:port
+    syn keyword schemeExtFunc exn:i/o:port:closed exn:i/o:tcp exn:i/o:udp exn:misc exn:misc:application exn:misc:unsupported exn:module exn:read
+    syn keyword schemeExtFunc exn:read:non-char exn:special-comment exn:syntax exn:thread exn:user exn:variable exn:application:mismatch
+    syn keyword schemeExtFunc exn? exn:application:arity? exn:application:continuation? exn:application:fprintf:mismatch? exn:application:mismatch?
+    syn keyword schemeExtFunc exn:application:type? exn:application:mismatch? exn:break? exn:i/o:filesystem? exn:i/o:port? exn:i/o:port:closed?
+    syn keyword schemeExtFunc exn:i/o:tcp? exn:i/o:udp? exn:misc? exn:misc:application? exn:misc:unsupported? exn:module? exn:read? exn:read:non-char?
+    syn keyword schemeExtFunc exn:special-comment? exn:syntax? exn:thread? exn:user? exn:variable? exn:application:mismatch?
+    " Command-line parsing
+    syn keyword schemeExtFunc command-line current-command-line-arguments once-any help-labels multi once-each 
+    hi def link schemeExtFunc PreProc
+
+    " syntax quoting, unquoting and quasiquotation
+    syn region schemeUnquote matchgroup=Delimiter start="#," end=![ \t\[\]()";]!me=e-1 contains=ALL
+    syn region schemeUnquote matchgroup=Delimiter start="#,@" end=![ \t\[\]()";]!me=e-1 contains=ALL
+    syn region schemeUnquote matchgroup=Delimiter start="#,(" end=")" contains=ALL
+    syn region schemeUnquote matchgroup=Delimiter start="#,@(" end=")" contains=ALL
+    syn region schemeUnquote matchgroup=Delimiter start="#,\[" end="\]" contains=ALL
+    syn region schemeUnquote matchgroup=Delimiter start="#,@\[" end="\]" contains=ALL
+    syn region schemeQuoted matchgroup=Delimiter start="#['`]" end=![ \t()\[\]";]!me=e-1 contains=ALL
+    syn region schemeQuoted matchgroup=Delimiter start="#['`](" matchgroup=Delimiter end=")" contains=ALL
+endif
+
 " Synchronization and the wrapping up...
 
 syn sync match matchPlace grouphere NONE "^[^ \t]"
@@ -181,6 +258,7 @@
   HiLink schemeConstant	Constant
 
   HiLink schemeComment		Comment
+  HiLink schemeMultilineComment	Comment
   HiLink schemeError		Error
 
   delcommand HiLink