PhantomJS can't use PDFJS

I am writing an angular-app, that uses Mozilla's library PDFJS. Unfortunately, when executing the unit-tests of the application, it seems that PhantomJS can't find parts of the PDFJS-lib.

Here is the error message:

PhantomJS 1.9.8 (Linux 0.0.0) ERROR
TypeError: 'undefined' is not a function (near '...}.bind(this), REJECTION_TI...')
at /home/[...]/bower_components/pdfjs-dist/build/pdf.js:1222

I need to use PhantomJS because of my CI infrastructure.