Alright, I made the switch from Tomato to DD-WRT just now. Had a HELL of a time getting the Asus WL-520GU with DD-WRT to recognize or initiate my PPPoE connection with my AT&T DSL connection. I had to reset the DSL modem twice for it to finally stabilize.

I sure hope this is the answer, I really could care less what firmware I use on my router as long as it's stable and it has DDNS. I disabled SPI and forwarded the familiar VOIPo Ports.