Load Balancing problem (same interface)

Load Balancing is not working if the gateway IP’s belong to the same interface.

example that does’nt work

dst-address=0.0.0.0/0 gateway=???.???.???.???,???.???.???.???
interface=real,real gateway-state=reachable,reachable scope=255
target-scope=10

example that works:

dst-address=0.0.0.0/0 gateway=???.???.???.???,???.???.???.???
interface=real,ipip gateway-state=reachable,reachable scope=255
target-scope=10

Thanks for feedback