[arch-general] Mounting tmpfs on /dev. Why?

Hi there. I'm newbie in Archlinux and I have another lame question. Recently, I've found that Arch mounts tmpfs on /dev. And, as you may see, this makes big problem to some applications. I see: "none on /dev type tmpfs" in the output of mount program. This mount is not placed in /etc/fstab. So, I think this is done by some of init scripts. I've looked at the /etc/rc.d folder and grep "mount" `find`. But nothing interesting found. I really don't want to mount tmpfs on /dev. How to don't do it? Thanks for patience.