Needs review
Source: Book of Exalted Deeds

Description: You can turn bonus damage into nonlethal damage.

Prerequisites: Subduing Strike

When you use your weapon to deal nonlethal damage, you can also transform bonus damage from a holy weapon, your smite evil class ability, or your smite granted power into nonlethal damage.

Special

A fighter may select Holy Subdual as one of his fighter bonus feats.