That's bad, because you couldn't use a SSI error page for 400 status code. Better one would be:if (!(ap_allow_options(r) & OPT_INCLUDES) || (r->status == HTTP_BAD_REQUEST)) {
if ((t = strrchr(r->filename, '/'))) {
to
if (r->filename && (t = strrchr(r->filename, '/'))) {
which fixes the actual problem.
nd