Tome of Magic Version
When a priest casts the 7th-level astral spell, he leaves his physical body in suspended animation while his astral body travels. By touching the comatose body and casting speak with astral traveler, a priest can mentally communicate with the projected individual. Although communication is mental, it takes the same amount of time as a normal, verbal dialogue. The spell ends abruptly when its duration expires.
Priest's Spell Compendium Version
A spellcaster who uses the astral spell (such as the 7th level priest spell) leaves his or her physical body in suspended animation while the astral body travels. By touching the comatose physical body and casting Speak with astral traveler, a priest can mentally communicate with the projected individual. Although communication is mental, it takes the same amount of time as a normal verbal dialogue. The spell ends abruptly when its duration expires.
Notes: Common for priests with access to the Astral sphere (ToM).