While this DM uses the grabbing an item and the sundering a carried or worn object rules as they're written, this DM extends the object saving throw rules to have effects that target a creature's attended objects treated as targeting the creature itself unless the effect says to do otherwise. For example, in this DM's campaigns, an efreet (that possesses the subtype fire) wearing (and therefore attending) gloves of dexterity renders its gloves of dexterity immune to fire damage.
Be aware that this house rule grew from a long discussion about whether PCs needed to acquire outfits that themselves possessed innate fire resistance so as to avoid roaming around naked on the Elemental Plane of Fire. Eventually I ruled that PCs' magical fire resistance extends to their outfits because—in addition to more serious reasons—efreeti aren't naked in their illustrations and burks still call it the City of Brass rather than thinking they're funny by dropping the Br. My campaigns have been better as a result of this ruling, and I've been using it for years with success.
So far as I'm aware, though, this is merely this DM's extension of the existing rules and never stated outright by the game. That makes the possibility of other tables making different rulings high. It's even possible a table never develops a general rule and decides everything case by case. This player wouldn't walk away from a campaign that ruled differently unless the DM were obviously and deliberately using the ruling to make the game less fun.
The spell turning spell and the spellblade ability are exceptions
The 7th-level Sor/Wiz spell spell turning [abjur] (Player's Handbook 282-3) says that a spell turning effect "turns only spells that have you as a target" (emphasis mine). In other words, even if a creature affected by a spell turning effect is attending an object, if that object is specifically targeted by a spell the spell turning effect won't protect that object.
For example, a creature protected by a spell turning effect would still see a druid destroy that creature's adamantine battleaxe were the druid to target it with the 4th-level Drd spell rusting grasp [trans] (PH 273) modified with the metamagic feat Reach Spell (Complete Divine 84). (The metamagic feat's necessary for the example as the spell turning spell "also [automatically] fails to stop touch range spells.")
The magic weapon special ability spellblade (Player's Guide to Faerûn 141) (6,000 gp; 0 lbs.) is far sloppier, though, than the spell turning spell. (Also see this question.) The spellblade description says that the spellblade's picked spell "must be one that is targeted against the wielder, not one that affects an area or creates an effect," yet after the spell's picked there's no limit on the spellblade ability's capacity to affect that spell.
This means that a DM that even allows the magic weapon special ability spellblade to be keyed to a spell that offers a variety of target choices, areas, or effects—like the 3rd-level Sor/Wiz spell dispel magic [abjur] (PH 223) does—must also decide how that works… and should tell the player before the PC buys a spellblade keyed to such a spell.
Specifically, in this DM's campaigns, the magic weapon special ability spellblade (dispel magic) doesn't affect dispel magic spells that target anything other than the spellblade's possessor. To be clear, that means in this DM's campaigns, by default, the wielder of +1 spellblade (dispel magic) kukri is protected from dispel magic spells, but the +1 spellblade (dispel magic) kukri remains itself vulnerable to dispel magic spells! While this ruling may sound like it makes the weapon special ability useless, this DM tries to keep his metagaming to a minimum, and folks that find the security the spellblade ability provides necessary don't usually find their +1 spellblade (dispel magic) gauntlet targeted by dispel magic spells.