Bè, ti servono un po' di varianti.
La prima è:
Dragonborn Paladin Substitution Level (RDr, p 108): gain knowledge: arcana
1st level: Detect Dragonblood, replaces detect evil
4th level: Bahamut's Blessing (bonus smiting dragons), lose turn undead
5th level: Fearless Special Mount
Poi aggiungerei anche:
Holy Warrior (CC, p 49): Lose spellcasting. Gain bonus feats.
Warded Special Mount (ECR, p 208): Lose one weekly use of remove disease. Mount becomes immune to negative energy and death effects.
E pure:
Planar Paladin (PlH, p 33): gain knowledge: the planes as a class skill
6th level: Celestial Mount (mount gains bonuses), lose remove disease