Several iterations of MK2 ago (in 2007), I was able to produce:

1. History
	1.1 Pre-Greek (Babylonian and Egyptian) sundials
	1.2 Greek and Roman sundials
	1.3 Byzantine sundials
2. Catalog (descriptions with photos, rough dating, evaluation)
	2.1 The Tower of the Winds and its sundials, treated separately
	2.2 General remarks on the cataloguing of the other finds
	2.3 Catalogue of the remaining finds on the Greek mainland and
	the Peloponnesus
3. Analysis
	3.1 Methodological remarks on the mathematical tools for analysis,
	and on their status
	3.2 Documentation of the results of the mathematical analysis of
	the measurements, comparison with other evaluations

using the following code (thanks to Aditya):

\setupitemize[1][fit,broad]
\setupitemize[2][width=2em]
\setupitemize[each][n]

\def\checkforrepeatedlistitem
 {\ifnum\itemlevel=\plusone
 \initializeboxstack{item}%
 \fi
 \ifconditional\repeatlistitem
 \savebox{item}{\itemlevel}{\hbox{\copy8}}%
 \setbox8\hbox %to \wd8
 {\setbox\scratchbox\hbox
 {\scratchcounter\itemlevel
 \advance\scratchcounter\minusone
 \dorecurse\scratchcounter{\foundbox{item}{\recurselevel}}}%
 \ifnum\itemlevel>\plusone
 \ifdim\wd\scratchbox>\zeropoint
 %\hskip-\dimen2
 \box\scratchbox
 \fi
 \fi
 \box8 }%
 \fi}

\startitemize[repeat,serried, joinedup]
 \item History
 	\startitemize[width=1.75em, stopper={}]
 	\item Pre{-}Greek (Babylonian and Egyptian) sundials
	 \item Greek and Roman sundials
	\item Byzantine sundials
 	\stopitemize
 \item Catalog (descriptions with photos, rough dating, evaluation)
 	\startitemize[width=1.75em, stopper={}]
 	\item The Tower of the Winds and its sundials, treated separately
	 \item General remarks on the cataloguing of the other finds
 	\item Catalogue of the remaining finds on the Greek mainland and the Peloponnesus
 	\stopitemize
 \item Analysis
 	\startitemize[width=1.75em, stopper={}]
	 \item Methodological remarks on the mathematical tools for analysis, and on their status
 	\item Documentation of the results of the mathematical analysis of the measurements, 
 	comparison with other evaluations
	\stopitemize
\stopitemize

But using 2010.08.06 22 of the minimals, I now get:

! Undefined control sequence.
\checkforrepeatedlistitem ->\ifnum \itemlevel 
                                              =\plusone \initializeboxstack ...

\dolistitem ...rutdepth \checkforrepeatedlistitem 
                                                  \ifdim \dimen 2<\zeropoint...

\complexdoitemgroupitem ...obreak \fi \dolistitem 
                                                  \relax \ifconditional \pac...
<to be read again> 
                   H
l.30  \item H
             istory

The redefinition of \checkforrepeatedlistitem was necessary because “serried” ruined the indentation of the subitems.

Is there a fix for this?

Alan