Admittedly, Pathfinder isn't 3.5, however the 3.5 SRD had different wording for Spring Attack.
3.5 SRD Spring Attack:Spring Attack [General] Prerequisites: Dex 13, Dodge, Mobility, base attack bonus +4.
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. Moving in this way does not provoke an attack of opportunity from the defender you attack, though it might provoke attacks of opportunity from other creatures, if appropriate. You can’t use this feat if you are wearing heavy armor.
You must move at least 5 feet both before and after you make your attack in order to utilize the benefits of Spring Attack.
A fighter may select Spring Attack as one of his fighter bonus feats.
There are two conclusions that I see...
1. The wording was deliberately changed to allow immunity to all opportunity attacks in Pathfinding from the target when using Spring Attack. This would likely be correct, as it would support the idea that the spring attack is of a surprising nature, though not surprising enough to cause the target to be flat-footed versus the attack.
2. The wording was changed without considering that the impact of the change in wording would lead to the target of a Spring Attack being unable to make opportunity attacks against the Spring Attacker. This is unlikely, as I think the designer(s) of Pathfinder would have made such wording changes for a reason.