Problem no longer existing. From another typeset text it later turned out to be the lack of \lbrack which manifested itself here as this error.
And of course I always try to make a minimal example in the first place as I know its importance, but will not succeed everytime.

Hans van der Meer

On 22 mrt 2010, at 18:14, Wolfgang Schuster wrote:

Am 22.03.10 11:01, schrieb Hans van der Meer:
I made use of descriptions in mkii. For example:
% Define the intro for the annotation
% Block opened on \startquestion and closed on \stopquestion
% \startannotation{} ... \stopannotation; {} required
\definedescription[annotationblock][%
\c!margin=\v!no,\c!location=\v!top,\c!width=\v!broad,%
\c!headstyle=\@@exmintrostyle,\c!style=\@@exmstyle,%
\c!before=,\c!inbetween=,\c!after=,%
\c!text=\placeannotationstart]
etcetera
http://www.tex.ac.uk/cgi-bin/texfaq2html?label=minxampl

Wolfgang

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