I'm looking at this again, after installing FreeBSD 8.0/amd64 in a VM.
I've reduced Lib/test/test_curses.py to the following 9 lines:
import rlcompleter
import curses
f = open('mytempfile', 'w+b')
stdscr = curses.initscr()
stdscr.putwin(f)
f.seek(0)
curses.getwin(f)
f.close()
curses.endwin()
I then get:
$ ./python Lib/test/regrtest.py test_curses
test_curses
Bus error (core dumped)
From looking at the core dump, and tracing through with gdb, the core dump occurs when delwin is called (from PyCursesWindow_Dealloc) on the result of curses.getwin(f), as a result of garbage collection.
The 'import rlcompleter' line appears to be necessary to cause this; I've no idea why.