knife specialization

[Soraksis]

what exactly is knife specialization and how do you get it? I heard it makes your daggers and kurkri's have the same crit threat as kopesh but I cannot find it anywhere in feats not sure how to unlock it please help.

[Arty_Farty]

It is an enhancement in the Rogue Assassin tree.

Knife Specialization: You gain a +1 Competence bonus to Critical Damage Multiplier with daggers and kukris. Daggers also gain a +1 Competence bonus to Critical Threat Range

http://ddowiki.com/page/Assassin_enhancements