Jack of All Trades( Complete Adventurer, p. 110)
You have picked up a smattering of even the most obscure skills.
You can use any skill as if you had 1/2 rank in that skill. This benefit allows you to attempt checks with skills that normally don't allow untrained skill checks (such as Decipher Script and Knowledge). If a skill doesn't allow skill checks (such as Speak Language), this feat has no effect.
Without this feat, you can't attempt some skill checks (Decipher Script, Disable Device, Handle Animal, Knowledge, Open Lock, Profession, Sleight of Hand, Speak Language, Spellcraft, Tumble, and Use Magic Device) unless you have ranks in the skill.