[luatex] tex.setskip

[Patrick Gundlach]

I wonder what is wrong with this texfile:

-----------------------------------------------------------------------------
\catcode`\{=1
\catcode`\}=2

\directlua{

  local myskip = node.new("glue",0)
  myskip.spec  = node.new("glue_spec")
  myskip.spec.width   = tex.sp("20pt")
  
  tex.setskip(5,myskip)

}

\end
-----------------------------------------------------------------------------


$ luatex --ini foo.tex 
This is LuaTeX, Version beta-0.60.1-2010052011 (TeX Live 2010/pretest) (rev 3685)  (INITEX)
 restricted \write18 enabled.
(./foo.tex
! LuaTeX error <\directlua >:1: incorrect value
stack traceback:
	[C]: in function 'setskip'
	<\directlua >:1: in main chunk.
l.13 }
      
? x


Patrick