Agree with Julius and Ian, I also think that it is some sort of enep (so called in Thailand), it will be such a knife from somewhere in the given area my two previous commentators have given. Compare with this one from Thailand:
http://www.vikingsword.com/vb/showth...highlight=enep and here one with not exact known origin:
http://www.vikingsword.com/vb/showth...light=thailand
But compare the general blade profile with all shown knives in this both threads.
Regards,
Detlef