MikroTik

Hey
I have X86 mikrotik
WAN = 192.168.1.1
LAN = 10.20.20.1/22
so, users IP's in subnet ( 10.20.20.2-10.20.23.254 )
My problem is :
How to make user ( 10.20.20.20 ) to see and ping user ( 10.20.22.22 )
although all of them on the same interface

It's already in place.
No icmp packets will hit the router.
Nor will the router be involved in the arp process beforehand.

-Chris