Needs review
Source: Frostburn

Description: You can smite creatures with the fire subtype

Prerequisites: Smite

Once per day, you may attempt to smite a creature with the fire subtype with a normal melee attack. When you activate this ability, your attack becomes infused with cold energy. You add your Charisma modifier to your attack roll and deal 1 extra point of cold damage per character level. If you smite a creature that does not have the fire subtype, the blast of cold does not manifest and the smite attempt is used up for that day. Remember that creatures with the fire subtype take half again as much (+50%) damage as normal from cold, including the additional damage dealt by this ability. You may swap out any daily uses of a smite ability gained by a character class or cleric domain to smite fiery foes instead.