I've read about backtraces, core dumps, and using gdb.
I'm no
programmer, so what is the best way for me to
troublesoot? $ gdb (gdb) file /usr/bin/kmail (gdb) run
<trigger the crash> (gdb) bt <you obtain the backtrace>
I don't know if this will be enough, but I'm not an expert debugger :).
I gave that a go. gdb reported that kmail exited normally. With some trial and error testing, I copied /usr/bin/kmail and /usr/lib/libkmailprivate.so from my Slackware 12.2 package and then the problem disappeared. At this point I can only guess that something in the kmail composer code does not compile correctly and instead causes the entire app to close rather than just the composer window.
Darrell