said by xPBxNaStY:forgot to mention theres only one NID also...can he still do it?
Yes. There are two pairs of wire going through the NID. The red/green pair is the primary line and would be "wet", i.e. have regular voice service on it. The other pair, black/yellow, is the secondary line and would be "dry."
The good news is that normally both pairs are wired throughout the house so at the jack where you want to plug in the "dry" DSL modem all you would have to do is replace it with a duplex jack (i.e. 2 RJ-11s), then wire the red/green pair to one jack for normal phone service and the black/yellow pair to the other jack for "dry" DSL.