Marshal and Draconic Auras

[Seerow]

So I'm building a Paladin who is dipping a couple levels into Marshal for some auras, and looking at the Marshal Handbook, I noticed that Draconic Aura is highlighted as a great feat for Marshals, as it gives another Aura to project. But when I looked it up in Dragon Magic, it says that Marshals have the option to take Draconic Auras in place of one of their normal Major Auras... which seems to imply that it is treated as a major aura and you can't have both a Draconic Aura and a Major Aura simultaneously. But nothing is really said about what happens if the Marshal takes the feat to gain a Draconic Aura like a different class would. Does he get it as a separate projectable Aura, or does it just add to his Auras Known? How does all of this interact with the Double Draconic Aura feat?


Also, are there any feats hidden somewhere I haven't been able to find that will give extra Marshal Auras known? Or any Marshal Multiclass feats? (I doubt the latter, but something like Devoted Commander to let Marshal and Paladin levels stack for Major Aura bonus and Smite Evil uses would be amazing)