extendedping: The next version will also have support for pre-close scripts, the same as the post-open scripts:

Place any (Maemo) commands you wish to run before you close the chroot into the /var/run/onclosechroot-ext.rc file (inside your rootfs),
Place any commands you wish to run from inside the chroot before you close the chroot into the /var/run/onclosechroot.rc file (inside your rootfs)