It isnt possible, The Nexus 1000v is a layer 2 distributed switch not a layer 3 switch.
If a VM needs to do OSPF it would need to form an adjacency with another OSPF capaable device on the same VLAN such as a real Cisco router or L3 switch (an upstream N7K or N5K with teh L3 duaghter card for example).
This would be the same as when using any other L2 switch to interconnect OSPF routers.
