That suggests that it was not part of rc4. I just installed a fresh rc4 and sure enough, whilte doing initial configuration of the system that bug hit me.
Sure, doing a qubes-dom0-update will fix this, but this bug makes it very hard to even begin to use the system and might reflect poorly on new users.
It would be nice if this fix was part of the final 4.0 release.
Regards,
Elias