diff --git a/runtime/syntax/debsources.vim b/runtime/syntax/debsources.vim
index e877b06..c8d110c 100644
--- a/runtime/syntax/debsources.vim
+++ b/runtime/syntax/debsources.vim
@@ -2,7 +2,7 @@
 " Language:     Debian sources.list
 " Maintainer:   Debian Vim Maintainers <pkg-vim-maintainers@lists.alioth.debian.org>
 " Former Maintainer: Matthijs Mohlmann <matthijs@cacholong.nl>
-" Last Change: 2014 Jul 11
+" Last Change: 2015 May 25
 " URL: http://anonscm.debian.org/hg/pkg-vim/vim/raw-file/unstable/runtime/syntax/debsources.vim
 
 " Standard syntax initialization
@@ -21,15 +21,35 @@
 " Match comments
 syn match debsourcesComment        /#.*/  contains=@Spell
 
+let s:cpo = &cpo
+set cpo-=C
+let s:supported = [
+      \ 'oldstable', 'stable', 'testing', 'unstable', 'experimental',
+      \ 'squeeze', 'wheezy', 'jessie', 'stretch', 'sid', 'rc-buggy',
+      \
+      \ 'precise', 'trusty', 'utopic', 'vivid', 'wily', 'devel'
+      \ ]
+let s:unsupported = [
+      \ 'buzz', 'rex', 'bo', 'hamm', 'slink', 'potato',
+      \ 'woody', 'sarge', 'etch', 'lenny',
+      \
+      \ 'warty', 'hoary', 'breezy', 'dapper', 'edgy', 'feisty',
+      \ 'gutsy', 'hardy', 'intrepid', 'jaunty', 'karmic', 'lucid',
+      \ 'maverick', 'natty', 'oneiric', 'quantal', 'raring', 'saucy'
+      \ ]
+let &cpo=s:cpo
+
 " Match uri's
 syn match debsourcesUri            +\(http://\|ftp://\|[rs]sh://\|debtorrent://\|\(cdrom\|copy\|file\):\)[^' 	<>"]\++
-syn match debsourcesDistrKeyword   +\([[:alnum:]_./]*\)\(squeeze\|wheezy\|jessie\|\(old\)\=stable\|testing\|unstable\|sid\|rc-buggy\|experimental\|devel\|lucid\|precise\|trusty\|utopic\)\([-[:alnum:]_./]*\)+
+exe 'syn match debsourcesDistrKeyword   +\([[:alnum:]_./]*\)\('. join(s:supported, '\|'). '\)\([-[:alnum:]_./]*\)+'
+exe 'syn match debsourcesUnsupportedDistrKeyword +\([[:alnum:]_./]*\)\('. join(s:unsupported, '\|') .'\)\([-[:alnum:]_./]*\)+'
 
 " Associate our matches and regions with pretty colours
-hi def link debsourcesLine            Error
-hi def link debsourcesKeyword         Statement
-hi def link debsourcesDistrKeyword    Type
-hi def link debsourcesComment         Comment
-hi def link debsourcesUri             Constant
+hi def link debsourcesLine                    Error
+hi def link debsourcesKeyword                 Statement
+hi def link debsourcesDistrKeyword            Type
+hi def link debsourcesUnsupportedDistrKeyword WarningMsg
+hi def link debsourcesComment                 Comment
+hi def link debsourcesUri                     Constant
 
 let b:current_syntax = "debsources"