diff --git a/runtime/syntax/xmath.vim b/runtime/syntax/xmath.vim
index a81adf5..22b3e85 100644
--- a/runtime/syntax/xmath.vim
+++ b/runtime/syntax/xmath.vim
@@ -1,11 +1,12 @@
 " Vim syntax file
 " Language:	xmath (a simulation tool)
 " Maintainer:	Charles E. Campbell <NdrOchipS@PcampbellAfamily.Mbiz>
-" Last Change:	Sep 11, 2006
-" Version:	7
+" Last Change:	Aug 31, 2016
+" Version:	9
 " URL:	http://www.drchip.org/astronaut/vim/index.html#SYNTAX_XMATH
 
-" quit when a syntax file was already loaded
+" For version 5.x: Clear all syntax items
+" For version 6.x: Quit when a syntax file was already loaded
 if exists("b:current_syntax")
   finish
 endif
@@ -191,34 +192,33 @@
 syn sync match xmathSyncComment	groupthere NONE "}#"
 
 " Define the default highlighting.
-" Only when an item doesn't have highlighting yet
-command -nargs=+ HiLink hi def link <args>
+if !exists("skip_xmath_syntax_inits")
 
-HiLink xmathBraceError	xmathError
-HiLink xmathCmd	xmathStatement
-HiLink xmathCommentBlock	xmathComment
-HiLink xmathCurlyError	xmathError
-HiLink xmathFuncCmd	xmathStatement
-HiLink xmathParenError	xmathError
+  hi def link xmathBraceError	xmathError
+  hi def link xmathCmd	xmathStatement
+  hi def link xmathCommentBlock	xmathComment
+  hi def link xmathCurlyError	xmathError
+  hi def link xmathFuncCmd	xmathStatement
+  hi def link xmathParenError	xmathError
 
-" The default methods for highlighting.  Can be overridden later
-HiLink xmathCharacter	Character
-HiLink xmathComma	Delimiter
-HiLink xmathComment	Comment
-HiLink xmathCommentBlock	Comment
-HiLink xmathConditional	Conditional
-HiLink xmathError	Error
-HiLink xmathFunc	Function
-HiLink xmathLabel	PreProc
-HiLink xmathNumber	Number
-HiLink xmathRepeat	Repeat
-HiLink xmathSpecial	Type
-HiLink xmathSpecialChar	SpecialChar
-HiLink xmathStatement	Statement
-HiLink xmathString	String
-HiLink xmathTodo	Todo
+  " The default methods for highlighting.  Can be overridden later
+  hi def link xmathCharacter	Character
+  hi def link xmathComma	Delimiter
+  hi def link xmathComment	Comment
+  hi def link xmathCommentBlock	Comment
+  hi def link xmathConditional	Conditional
+  hi def link xmathError	Error
+  hi def link xmathFunc	Function
+  hi def link xmathLabel	PreProc
+  hi def link xmathNumber	Number
+  hi def link xmathRepeat	Repeat
+  hi def link xmathSpecial	Type
+  hi def link xmathSpecialChar	SpecialChar
+  hi def link xmathStatement	Statement
+  hi def link xmathString	String
+  hi def link xmathTodo	Todo
 
-delcommand HiLink
+endif
 
 let b:current_syntax = "xmath"