Rusting Grasp and Melee Weapons

[Burke]

As far as I know this hasn't been significantly changed for 3.5, but if it makes a difference this is for a 3.0 game.

So, I can't figure out how Rusting Grasp works when used against an opponent's weapon. Here's the relevant part of the 3.0 SRD:

Weapons in use by an opponent targeted by the spell are more difficult to grasp. The character must succeed at a melee touch attack against the weapon. A metal weapon that is hit is instantaneously destroyed. Note: Striking at an opponent’s weapon provokes an attack of opportunity. Also, the character must touch the weapon and not the other way around.

So, what's a melee touch attack in this context? The section in the PHB about touch spells in combat doesn't address touching an object or weapon, and I can't find anything in the Magic chapter about it either. There's also sections for striking a weapon and disarming in the Combat chapter, but neither of those options seem conceptually similar, and neither of them discuss touch attacks versus a weapon.

 

[The Grackle]

Attacking a held, carried, or worn object provokes an attack of opportunity. Objects that are held, carried, or worn by a character, are harder to hit. The object uses the character's Dexterity modifier (not its own –5) and any magic deflection bonus to AC the character may have. The attacker doesn't get any special bonus for attacking the object. If the target object is in the opponent's hand, it gets a +5 AC bonus because the opponent can move it quickly out of harm's way.
Table: Size and AC of Objects
Size AC Modifier
----- -----------
Colossal -8
Gigantic -4
Huge -2
Large -1
Medium-size +0
Small +1
Tiny +2
Diminutive +4
Fine +8

It looks like everything that applies to the weapon's AC (deflection, dex, size, and a special +5 bonus) should all apply to a touch attack or a normal attack equally.

 

[Burke]

Hmm, maybe. After thinking about it some since my first post, I'm leaning towards using the "striking an opponent's weapon" rules, primarily because the spell description includes the words "Striking at an opponent’s weapon". Though, as that's just an opposed attack roll, I don't understand why they used the phrase "melee touch attack", as that normally has a very specific meaning relating to what type of AC bonuses apply, but perhaps I'm overthinking it.