OpenWRT and DSL together?

Question

network hardware

There is an ADSL router Asus WL600G. I found OpenWRT firmware on it ( wiki.openwrt.org/toh/asus/wl600g).
Having installed it, I discovered that OpenWRT does not support "out of the box" dsl.
How to be? I read somewhere that something like multiwan can help. Is it so?
Or if I understood something wrong, what should the interface of the dsl-cable (telephone) be called and where should I turn it on?
Thanks in advance for your help.