Hi,

I tried the following snipped out of curiosity and it gives me the error 
(even with the latest beta)

systems : begin file 1.tex at line 5

(c:/contextminimal/texmf-context/tex/context/sample/knuth.tex) 
(c:/contextminimal/texmf-context/tex/context/sample/knuth.texerror: 
...tminimal/texmf-context/tex/context/base/typo-krn.lua:121: attempt to 
index local 'before' (a nil value)

.

l.11

?


> \definecharacterkerning[packed]
>
> \setupcharacterkerning[packed][factor=-.125]
>
> \starttext
>
> \input knuth
>
> \start
>
> \setcharacterkerning[packed]
>
> \input knuth
>
> \stop
>
> \stoptext
>

What have I missed?

Regards,
Vyatcheslav