http://www.d20srd.org/srd/spells/magesDisjunction.htm
So, the obvious thing I must ask, is WHY develope a spell in a 9th level slot, that is doing what Dispel, grtr Dispel, or Anti Magic SHOULD already be doing?
If its NOT permanent, and its ONLY single target, then why not just Make Dispel Magic do this?
Thats all your doing anyway, giving up dispel magic, but in a 9th level spell slot.
Dispel Magic
Abjuration
Level: Brd 3, Clr 3, Drd 4, Magic 3, Pal 3, Sor/Wiz 3
Components: V, S
Casting Time: 1 standard action
Range: Medium (100 ft. + 10 ft./level)
Target or Area: One spellcaster, creature, or object; or 20-ft.-radius burst
Duration: Instantaneous
Saving Throw: None
Spell Resistance: No
You can use dispel magic to end ongoing spells that have been cast on a creature or object,
to temporarily suppress the magical abilities of a magic item, to end ongoing spells (or at least their effects) within an area, or to counter another spellcaster’s spell. A dispelled spell ends as if its duration had expired. Some spells, as detailed in their descriptions, can’t be defeated by dispel magic. Dispel magic can dispel (but not counter) spell-like effects just as it does spells.
Make this work, dont just do it in a 9th slot and call it Disjuntion, cause it aint even close.