Ashtagon
Adventurer
also it is already designated in the AaEG (arms and equipment guide) that it deals lethal damage. so my question still remains, given its new-found ability to be letal, does it threaten?
Given that there are non-lethal weapons that do threaten (sap in SRD), I'd say that whether or not a weapon does lethal damage is not relevant to determining whether or not it threatens an AoO.