'German Double s' character trouble

[Willadt@t-online.de (Peter Willadt)]

Hello,

using context 1999-09-30 I encounter the following problem with the
german-double-s character (ß) (I hope it shows up correctly in your
email, it should look similiar to an upright beta):

Using [win] as encoding, ß shows up as dotless i.
Using [ans] as encoding, ß shows up as SS.
Saying \ss like in plain TeX, context switches to sanserif instead of
displaying any character.
Saying \3 like in german.sty, context complains about an unknown
command.

My setup is like shown below:

\useencoding[win]
\setupoutput[pdftex]
\setupbodyfont[ber, ptm]
\de
\usemapping[texnansi]
some text containing 'ß' 

And, if I remember correctly, the first alternative once worked with an 
elder context version.
Thanks in advance for any hints.

Peter Willadt