Installation on OSX El Capitan fails

[vgire]

Hello, I am trying to move from python's pjsip biddings to sipster, but I get the following error:

$ npm install sipster
> [email protected] install /Users/vincentgire/Documents/Projects/sensout/proto/phone/node_modules/sipster
> node-gyp rebuild

  CXX(target) Release/obj.target/sipster/src/binding.o
../src/binding.cc:6:10: fatal error: 'pjsua2.hpp' file not found
#include <pjsua2.hpp>
         ^
1 error generated.
make: *** [Release/obj.target/sipster/src/binding.o] Error 1
gyp ERR! build error 
gyp ERR! stack Error: `make` failed with exit code: 2
gyp ERR! stack     at ChildProcess.onExit (/usr/local/lib/node_modules/npm/node_modules/node-gyp/lib/build.js:270:23)
gyp ERR! stack     at emitTwo (events.js:87:13)
gyp ERR! stack     at ChildProcess.emit (events.js:172:7)
gyp ERR! stack     at Process.ChildProcess._handle.onexit (internal/child_process.js:200:12)
gyp ERR! System Darwin 15.0.0
gyp ERR! command "/usr/local/bin/node" "/usr/local/lib/node_modules/npm/node_modules/node-gyp/bin/node-gyp.js" "rebuild"
gyp ERR! cwd /Users/vincentgire/Documents/Projects/sensout/proto/phone/node_modules/sipster
gyp ERR! node -v v5.4.1
gyp ERR! node-gyp -v v3.0.3
gyp ERR! not ok 
npm WARN EPACKAGEJSON [email protected] No description
npm WARN EPACKAGEJSON [email protected] No repository field.
npm WARN EPACKAGEJSON [email protected] No license field.
npm ERR! Darwin 15.0.0
npm ERR! argv "/usr/local/bin/node" "/usr/local/bin/npm" "install" "sipster"
npm ERR! node v5.4.1
npm ERR! npm  v3.3.12
npm ERR! code ELIFECYCLE

npm ERR! [email protected] install: `node-gyp rebuild`
npm ERR! Exit status 1
npm ERR! 
npm ERR! Failed at the [email protected] install script 'node-gyp rebuild'.
npm ERR! Make sure you have the latest version of node.js and npm installed.
npm ERR! If you do, this is most likely a problem with the sipster package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR!     node-gyp rebuild
npm ERR! You can get their info via:
npm ERR!     npm owner ls sipster
npm ERR! There is likely additional logging output above.

npm ERR! Please include the following file with any support request:
npm ERR!     /Users/vincentgire/Documents/Projects/sensout/proto/phone/npm-debug.log

It seems the pjsua library headers are not found but pkg-config does recognize pjproject as being installed.

My system is OSX El Capitan 10.11.1 with:

$ node -v
v5.4.1

$ npm -v
3.3.12

$ pkg-config --version
0.28

$ pkg-config --modversion libpjproject
2.4.5

I have installed pjsip with:

tar xvjf pjproject-2.4.5.tar.bz2
cd pjproject-2.4.5
./configure --enable-shared && make dep && make clean && make && make install

Any help would be really appreciated.

Thanks