False Sending

The caster contacts a particular creature with whom she is familiar and sends a short message of twenty-five words or less to the subject. The subject is convinced that the sender of the message is someone other than the caster, as specified by the caster.

Book of Vile Darkness 3.5
By Monte Cook

Illusion (Glamer)

Level: Cleric 5, Sorcerer/Wizard 6
Components: V, S, M/DF
Casting Time: 10 minutes
Range: See text
Target: One creature
Duration: 1 round (see text)
Saving Throw: Will negates
Spell Resistance: Yes

The caster must be also familiar with the false sender. The subject can answer in like manner immediately. Creatures with Intelligence scores as low as 1 can understand the false sending, though a subject’s ability to react is limited normally by its Intelligence. Even if the sending is received, the subject creature is not obligated to act upon it in any manner.

If the creature in question is not on the same plane of existence as the caster, there is a 5% chance that the sending does not arrive. (Local conditions on other planes may worsen this chance considerably, at the option of the DM.)

Arcane Material Component: A short piece of corroded copper wire.