Dha with this style of blade are not uncommon. usually they are associated with the Kachin Look at sword 231 and 232 here
http://www.arscives.com/historysteel....swordlist.htm
Several others can be found on Marks index here
http://dharesearch.bowditch.us/SwordsFrame1Source1.htm
I have never seen one with an oval hilt but maybe others have or maybe it was originally round and was "flattened" a bit by something that happened to it