[pdftex] hyperref and customized section formatting

[Martin Jansche]

Hi,

I've run into a problem involving pdflatex, hyperref, and my need for
custom formatting of section headings: if I \renewcommand{\chapter} to
implement strange formatting requirements, I start getting warning
messages ("Package hyperref Warning: No destination for bookmark of
\addcontentsline...") corresponding to code fragments like

  \chapter*{Unnumbered chapter}
  \addcontentsline{toc}{chapter}{Unnumbered chapter}

The end result is that hyperlinks from the table of contents to
"Unnumbered chapter" are broken.

What would be an appropriate way to change the default appearance of
section titles?  Does hyperref redefine the sectioning commands?
(Yes, I've looked at the source.  I still don't know.)  If so, which
macros should I redefine, if all I want is to change the layout of the
section title without affecting any hyperref magic?

Thank you, and apologies if this turns out to be mostly a hyperref
question.

- martin