Error building `zmq_exec.c`

Trying to build `zmq_exec.c` on OS X, MATLAB R2015b and ZMQ 4.1.4, getting the following error.

```
Error using mex
/Users/abhijithc/.julia/v0.4/julia-matlab/mex/zmq_exec.c:55:32: error: too few arguments to function call, expected 4,
have 3
  rc = zmq_send(socket, &msg, 0);
       ~~~~~~~~                ^
/usr/local/Cellar/zeromq/4.1.4/include/zmq.h:353:1: note: 'zmq_send' declared here
```
