Traveler’s Mount

With words of encouragement, you make the creature better able to handle the rigors of overland travel, at the expense of its ability to fight.

(Spell Compendium, p. 223)  
Originally posted on D&D tools

Transmutation

Level: Blackguard 1, Druid 1, Paladin 1, Ranger 1,
Components: V, S,
Casting Time: 1 standard action
Range: Touch
Target: Animal or magical beast touched
Duration: 1 hour/level
Saving Throw: Will negates
Spell Resistance: Yes

The touched animal or magical beast gets a 20-foot enhancement bonus to its speed, and it can hustle without taking damage or becoming fatigued as long as the spell is in effect. While bearing a rider, the mount no longer attacks in combat. The steed willingly bears its rider into battle; it just can’t use its own natural weapons for the duration of the spell.