A spellthief (Complete Adventurer 13) cannot apply metamagic feats to stolen spells. The ability steal spells reads, in part:
A spellthief can't apply metamagic feats or other effects to the stolen spell unless the specific spell stolen was prepared with such an effect. For example, a spellthief of 6th level or higher could steal a wizard's empowered magic missile, but only if he specifically chose to steal empowered magic missile. If he chose to steal an unmodified magic missile, he couldn't steal an empowered magic missile, a silent magic missile, or any other metamagic form of the spell. A spellthief couldn't steal an empowered magic missile from a sorcerer, since the sorcerer applies metamagic effects upon casting and thus has no prepared empowered magic missile spell.
Does this apply to metamagic feats in general? Can a spellthief use a metamagic rod in conjunction with a stolen spell?