While riding an intelligent mount, while your character undertakes his normal actions (such as draw a weapon, attack, etc), what happens if the mount uses its move action to move and then uses its standard action to ready an action, for example to avoid an attack or to move if any creature comes close?
According to the rules you and your mount share the same initiative count (meaning that both of you share the turn) but if the mount uses ready an action, does the initiative change for both you and your mount? Or are you acting on different initiative counts now? If you act on different counts it seems unclear how that interacts with things like mounted archery penalties that happen "while your mount is moving", as those all assume you and your mount are acting at the same time.
According to this: http://archive.wizards.com/default.asp?x=dnd/rg/20050222a
According to the Dungeon Master's Guide, a mount with an Intelligence score of 3 or higher acts like an NPC ally rather than a mount. Riding such an ally works much like riding an aggressive mount in battle (see Part Two), except that you don't have to make a Ride check to act while riding. (If your mount carries you willingly, the ride is smooth enough so your actions aren't restricted.) You also cannot make a Ride check to control the mount's actions, but you can make a Diplomacy (or possibly a Wild Empathy) check to get the mount to accept your direction. If you do, your mount acts just like a mount trained for combat riding.
Aggressive Mounts in a Battle
A character could ride a mount that isn't cowardly in battle, but still isn't trained to carry a rider into combat. For example, a riding dog might be inclined to fight when danger threatens. If you're a druid or ranger, you might use your wild empathy ability (and maybe a speak with animalsspell or two) to induce some big carnivore to give you a lift. If you find yourself in a battle while still astride your mount/ally, you and your improvised mount still act on your initiative number. You must attempt a Ride check to direct the mount's actions, which is noted in the section on unruly mounts. If you fail, the mount might stick around to fight. If so, the mount moves where it will, but you still can't take any other action in the same round that you made the failed check (you spend your time just staying on).