Spell Sunder +Greater Sunder = full damage to target?

[Sirlink]

So I am trying to put together a Sunder Barbarian build and I am looking for clarification. How do Spell Sunder and Greater Sunder interact?
Spell Sunder: Once per rage, the barbarian can attempt to sunder an ongoing spell effect by succeeding at a combat maneuver check. For any effect other than one on a creature, the barbarian must make her combat maneuver check against a CMD of 15 plus the effect’s caster level. To sunder an effect on a creature, the barbarian must succeed at a normal sunder combat maneuver against the creature’s CMD + 5, ignoring any miss chance caused by a spell or spell-like ability. If successful, the barbarian suppresses the effect for 1 round, or 2 rounds if she exceeded the CMD by 5 to 9. If she exceeds the CMD by 10 or more, the effect is dispelled.

+
Greater Sunder : You receive a +2 bonus on checks made to sunder an item. This bonus stacks with the bonus granted by Improved Sunder. Whenever you sunder to destroy a weapon, shield, or suit of armor, any excess damage is applied to the item's wielder.

Does this mean that when you dispel an effect completely you then apply damage to the target?

[fictionfan]

Sirlink wrote:

Greater Sunder : You receive a +2 bonus on checks made to sunder an item. This bonus stacks with the bonus granted by Improved Sunder. Whenever you sunder to destroy a weapon, shield, or suit of armor, any excess damage is applied to the item's wielder.

Unless the ongoing spell effect is a weapon, shield, or suit of armor nothing happens. There are some conjured magical weapons and mage armor could be agued to be armor.

[kinevon]

Since Spell Sunder doesn't do damage, just suppresses the magical effect for a short time, there is no excess damage for Greater Sunder to apply.