I'm interested to know whether nested sections are supported in the new structure code (strc-*)?

Using the following to test, I don't get a section and subsection, but rather two sections. The log file notes a "missing \stopsection".

\starttext
\startsection{Section}
\input tufte
\startsection{Subsection}
\input knuth
\stopsection
\stopsection
\stoptext

Am I missing a setup command somewhere in the new structure code that enables nested sections?

Thanks,

Kevin