diff --git a/runtime/syntax/jgraph.vim b/runtime/syntax/jgraph.vim
index 7ecd5af..43fc427 100644
--- a/runtime/syntax/jgraph.vim
+++ b/runtime/syntax/jgraph.vim
@@ -5,11 +5,8 @@
 " this syntax file is not yet complete
 
 
-" For version 5.x: Clear all syntax items
-" For version 6.x: Quit when a syntax file was already loaded
-if version < 600
-  syntax clear
-elseif exists("b:current_syntax")
+" quit when a syntax file was already loaded
+if exists("b:current_syntax")
   finish
 endif
 
@@ -36,23 +33,15 @@
 
 
 " Define the default highlighting.
-" For version 5.7 and earlier: only when not done already
-" For version 5.8 and later: only when an item doesn't have highlighting yet
-if version >= 508 || !exists("did_jgraph_syn_inits")
-  if version < 508
-    let did_jgraph_syn_inits = 1
-    command -nargs=+ HiLink hi link <args>
-  else
-    command -nargs=+ HiLink hi def link <args>
-  endif
+" Only when an item doesn't have highlighting yet
+command -nargs=+ HiLink hi def link <args>
 
-  HiLink jgraphComment	Comment
-  HiLink jgraphCmd	Identifier
-  HiLink jgraphType	Type
-  HiLink jgraphNumber	Number
+HiLink jgraphComment	Comment
+HiLink jgraphCmd	Identifier
+HiLink jgraphType	Type
+HiLink jgraphNumber	Number
 
-  delcommand HiLink
-endif
+delcommand HiLink
 
 
 let b:current_syntax = "jgraph"