In memoir, can I number abstracts as sections in the toc?

Question

I'm writing up my thesis right now, using memoir, and I have a problem with abstracts. Each chapter - besides the intro and conclusion - is an article published in a journal, and has its own abstract (which is in addition to the abstract at the beginning of the thesis). I like the way the abstract environment \begin{abstract}... typesets the abstracts for each chapter, but they show up as unnumbered chapters in the table of contents. If I use \abstractnum to force numbering it just numbers the abstracts as chapters; what I'd really like is for them to be numbered as sections:

2 Great chapter title
2.1 Abstract ....
2.2 Introduction ....
[...]

I've been up one side of Google and down the other to no avail, and I can't find anything in the memoir manual. Is there a simple way to do this in memoir, or do I have make the abstracts \section{}s and live with it?

Update:

I've been playing more and I can get the behaviour I want in individual chapters if I muck with the section numbering and add to the toc manually:

\begin{abstract}
\addtocounter{section}{1}
\addcontentsline{toc}{section}{\numberline{\thesection}Abstract}
...

But now I've got the opposite problem: I put the thesis abstract in the table of contents using \abstractintoc before the thesis abstract, but now the chapter abstracts show up twice, once as an unnumbered chapter and once as the properly numbered section:

2 Great chapter title
Abstract
2.1 Abstract..
2.2 Introduction...

Maybe it's easier to solve the problem when it's this way instead?

Answer 1

Besides calling \abstractnum, you can redefine \num@bs:

\makeatletter
\renewcommand*{\num@bs}{\section{\abstractname}}
\makeatother

It's originally defined in memoir.cls:

\newcommand{\num@bs}{\chapter{\abstractname}}

Instead of simply redefining this internal macro, you could create your own abstract environment using \renewenvironment{abstract}{...} and calling \section within.

As said in the comment, here's a minimal example:

\documentclass{memoir}
\abstractnum
\makeatletter
\renewcommand*{\num@bs}{\section{\abstractname}}
\makeatother
\listfiles
\begin{document}
\tableofcontents
\chapter{One}
\begin{abstract}
   Here is the abstract.
\end{abstract}
Text follows.
\end{document}

Answer 2

Hendrik asked me to move this to a separate answer, so here it is...

Update: Following Stefan's awesome answer:

The minimal example you provided didn't quite work, Stefan, because I still need the thesis abstract and I need it unnumbered. But here's a minimal example that does work for me:

\documentclass{memoir}
\makeatletter
\renewcommand*{\num@bs}{\section{\abstractname}}
\makeatother

\listfiles
\begin{document}
\tableofcontents
\clearpage
\abstractintoc
\begin{abstract}
Here's the thesis abstract.  Should be unnumbered.
\end{abstract}

\abstractnum
\chapter{One}
\begin{abstract}
    Here is the chapter abstract.  Should be (and is) numbered.  
\end{abstract}
\section{Introduction}
Text follows.
\end{document}

Seems to work for me, so I'm going to go with that. :-)