[Freeswitch-users] How to call multi gateways for failover with early media?

Hi, I have outbound gateways returns 403 or 503 constantly. So I tried to dial out using sofia/gateways/gw1/xxxx|sofia/gateways/gw2/xxxx|sofia/gateways/gw3... for fail over. To make it work, I need to set ignore_early_media=true. However, the caller do need to hear the early media to figure out what's going on. If I set ignore_early_media=false, only the first one tried. A little more detail: The gateway is first tier, if it cannot initiate a PSTN channel returns 403/503 immediately. If it can find a PSTN channel, but the callee fails, no answer or busy or others, it plays early media and returns 503. If I want failover, and the early media, how to do that? Thanks. regards, Seven.