Casters Lament

Warlock Invocation
Level: Dark, 8th
Components: V, S
Casting Time: 1 standard action
Range: Self
Duration: Instantaneous
Saving Throw: None
Spell Resistance: No

You can produce a break enchantment effect (as the spell) with your touch. You can only attempt to affect any single magical effect—an ongoing spell, a permanent transformation, a magic item, or the like—once per 24-hour period.
In addition, you can use casters lament to counterspell another caster's spell (of 7th level or lower) as if casting greater dispel magic.

(Complete Mage, Page 123)