httpPost with multipart/form-data

It was asked in developer forum but got no answer.
even the answer is negative, I think it is an easy question to answer. yes/no

so, the question is :
is it possible to send http post with multipart/form-data

When I try it, hub does not produce any http packet.
I mean if I set
requestContentType: "multipart/form-data; boundary=--abcdefg",

so is this not supported ?

if that's the case, can we create a raw http packet without using httpPost ?