How I understand this: take first vertex and take first normal for this face index. And take first vertex and take 496-th normal for this face index (second case).
For example take 1-st vertex - and we can see that this vertex can share data 1//1 and also 1//496!!!
But it's impossible in actionScript to tell GPU to use 1-st normal for 1-st vertex as wel as 496-th normal for the same 1-st vertex. Please correct me if I wrong.
Upd.: I rephrase my question. In the link to obj model array in face instructions points to the same vertex, but different normals. Is it ok that vertext have 2 normals?