I rebuilt rxvt-unicode with the patch and the urxvt segfaults at exit no longer occurs. For me this is fixed.
--- a/src/rxvtperl.xs.orig +++ b/src/rxvtperl.xs @@ -376,6 +376,7 @@ rxvt_perl_interp::~rxvt_perl_interp () { if (perl) { + localise_env set_environ (perl_environ); perl_destruct (perl); perl_free (perl); PERL_SYS_TERM (); Cheers Holger...