As I said earlier
»Re: [Tomato] WRT54GL Tomato - How Do I Access the DSL Modem? worked, here. Yipe
While I have a hub/switch that I could use and I have a Static Public IP, I suspect that on PPPoE with tomato firmware you can access the modem combo while the modem combo is in bridge mode.
Before I got a Static Public IP, I did not test this with PPPoE. So, I can't say for sure this will work.
Please use the "yellow (IM) envelope" to contact me and please leave the URL intact.