Ipod touch .caf help...i think.?

Well...I am trying to make my custom lock and unlock sounds for my ipod touch....Ive ssh'd into my ipod and put the unlock.caf and lock.caf files in to the UI sounds folder under crystal voice.....the problem is that I don't get any sound when I lock or Unlock my Itouch.....I tried downloading other lock sounds from cydia and they don't even work....please help!