UMD and Runestaves?

[Zaq]

Runestaves (I refuse to say Runestaffs... I'm aware of the general tendency in English to have invented words use standard pluralization and conjugation rather than that of the base word --compare talking about cops as "flatfoots" rather than "flatfeet" -- but that doesn't change the fact that "Runestaffs" sets off my native speaker intuition and just sounds dumb.), from Magic Item Compendium, are a nifty item that lets you essentially channel one of your own spells or spell slots into it and get a different, pre-determined spell out. Could a UMD user invoke the "imitate class feature" function of UMD to use one of the spells stored in a runestaff? The question comes down to whether the runestaff changes the spell you can cast, or casts the spell itself if you meet its trigger condition of casting the spell into it. To me, the issue is unclear. What do you folks think?

[monty]

Using a runestaff requires sacrificing an actual spell slot. Since UMD can only let you emulate the spellcasting class feature, and not the spell slots themselves, you could not do this.

I believe you could, however, use UMD to use a runestaff for a spell that's not on your class list, although this probably isn't what you're looking for.

[Anyr]

From the text in the MIC, it seems fairly clear that the person wielding the runestaff is the one that casts the spell. Not only do they need an open slot which is expended on casting, they also have to provide any material components and spend XP on it. Also, they can freely apply metamagic if they have a sufficiently high slot available. All these things are at odds with the usual way that spell trigger/completion items work and support the interpretation that the runestaff just gives casters a new way to expend the magical energy they already have, rather than providing any themselves.

[Chronos]

A Beguiler can use UMD on a Runestaff to expand his limited spell list, since he still has slots to give up, but a Rogue can't do a thing with them, since he doesn't have any slots to give up. UMD by itself just gives you the ability to sacrifice a spell slot for a spell from the staff; it doesn't give you the slot to give up.