Dear Taco and list,

I have a problem (with the latest minimals) sorting bibtex entries:

Consider the following example:

% bibbug.tex
\usemodule[bib]

\setuppublications[
	sorttype=bbl,
]

\setupbibtex[
	database=mp,
]

\starttext
See~\cite{resi3,resi4} and also~\cite{resi2,resi1}.

\placepublications[criterium=all]
\stoptext
% end of bibbug.tex

I get an eror:
! LuaTeX error ...TeXt/tex/texmf-context/tex/context/base/bibl-tra.lua:83:
attempt to compare two nil values
stack traceback:
	...TeXt/tex/texmf-context/tex/context/base/bibl-tra.lua:83: in
function <...TeXt/tex/texmf-context/tex/context/base/bibl-tra.lua:80>
	[C]: in function 'sort'
	...TeXt/tex/texmf-context/tex/context/base/bibl-tra.lua:93: in function 'flush'
	<main ctx instance>:1: in main chunk.
\typesetpubslist ...hacks.flush("\@@pbsorttype ")}
                                                  \doendoflist
\dodoplacepublications ...sttrue \typesetpubslist
                                                  \inpublistfalse \endgroup ...
l.14 \placepublications[criterium=all]

If I uncomment the sorttype=bbl line, it compiles.

Attached is the tex file, the log file, and my bib file.

Best regards, Mikael