Improved Stunning Fist [General]

Your stunning attacks are sometimes powerful enough to jar an opponent so badly that he loses control over his legs and crumples into a heap.
Prerequisite: Stunning Fist
Benefit: If an opponent fails his saving throw against your stunning attack by 5 or more, he falls prone in addition to the normal penalties associated with being stunned.
Special: A monk may select Improved Stunning Fist as a bonus feat at 6th level. A fighter may select Improved Stunning Fist as one of his bonus fighter feats.