There are a few key points in the feat description for Spring Attack.
When using the attack action with a melee weapon, you can move both before and after the attack, provided that your total distance moved is not greater than your speed.
Attack Action is not the same as Full Attack.
Speed is not the same as Move Action.
This is one of the reasons why 3.5 Haste increases your speed instead of providing bonus actions. (Another huge reason was for spells.) If the Hustle talent simply boosted your speed by 30', like Haste and Expeditious Retreat, the interaction with Spring Attack would be much more apparent.
Alas, it is not. One option would be to house rule Hustle so it acts like Haste or Expeditious Retreat.
Unfortunately, when you start looking at complex interactions between feats, you have to be very precise in your reading & interpretation. Remember that one of the benefits of Feats is that they may break the normal rules. The question then becomes what the intended "break effect" is. In the case of Combat Reflexes, the "break" is apparent: You get more than 1 AOO/round.
In the case of Spring Attack, you are allowed to move, attack and move up to your normal speed. Normally, you must attack then move, or move then attack. Spring Attack, as a feat with a long string of prerequisites also provides a secondary benefit: You do not incur an AOO from your target as you move near and then leave a threatened zone. So, Spring Attack provides two benefits: an attack during your move, and avoiding the AOO that might come from your movements. These are very specific benefits and powerful ones. Note that you can still incur AOO's from other opponents during a Spring Attack, just not from the opponent you attacked.
Hustle breaks the rules by allowing an additional move. This means you can move, attack, move and emulate part of the benefits from Spring Attack. However, you still incur AOO's from the opponent you attacked. As well, you could move, full attack. Or full attack and move.
Now the interaction between Hustle and Spring Attack is the question. Remember though, that all Hustle does is give you an additional move. It does not increase your speed, so it does not interact with Spring Attack perfectly. Spring Attack is very specific that it's benefits only apply to an attack (not a full attack) so long as you do not exceed your speed (not as long as you have move actions left.)
These are very precise readings, but they need to be. In no case will you be able to use this feat combination to Spring Attack, get a Full Attack action and move without incurring an AOO.
Rules interactions are not always easy. But that is the role of the DM and that is why there are so many rules threads here. Understanding the interactions will allow you to understand the "official interaction" of the feats and then decide how you want to house rule it, if appropriate.