I've rebuilt the 1.3.1 kernels to fix the ioasic clock problem,
updated the diskimage .gz file and tarball to 1.3.1, and put them on
ftp.netbsd.org in ~ftp/pub/NetBSD/NetBSD-1.3.1/pmax.

Everything should now be ready to go for 1.3.1 installs, except for
the X11 sets.  For now, please install the X11 sets from 1.3.

The fixes for fvwm and twm are actually in the updated ld.so, so you
don't need updated x11 sets to fix the problems with fvwm/twm.