Today I bartered a set of Boots of Sprinting (3 charges) to a character. As far as I could tell, the barter was normal and everyone clicked okay. Just the boots were being bartered, nothing else. Instead of him recieving the item I got a set of boots in my inventory that were unidentified and of a completely differant look. Upon identification the new set of boots were Boots of Elvenkind (+2 dex +10 MS.)
To say my jaw dropped was an understatement. Howland said this was a bug and should be reported. He also mentioned that the head of the seekers, who was nearby at the time had a set of Elvenkind boots just like the pair that appeared in my inventory.