Bug: /dev/shm does not use /etc/fstab attributes after reboot in RHEL 6

There is a bug in Red Hat Linux 6 and Oracle Enterprise Linux 6 (UEK and RHEL-kernel).
When you need more memory for SGA/PGA when using MEMORY_MAX_TARGET, you need to resize /dev/shm. By default this is 50% of total memory and Oracle tells you to add the following to /etc/fstab:

tmpfs    /dev/shm     tmpfs   defaults,size=3G  0 0

This works after a remount:

mount -o remount /dev/shm

but it doesn’t work after a reboot.
Fix:
add

mount -o remount /dev/shm

in /etc/rc.d/rc.sysinit file at the end and /dev/shm will have attributes from /etc/fstab after reboot.