usemin option uglifyjs error "Maximum call stack size"

Hi,
when I try the usemin option it seems to be failing:
Gruntfile code:

ngtemplates:  {

      app: {

        src: '<%= yeoman.app %>/templates/**/*.html',

        dest: '.tmp/templates.js', 

        options:  {

          htmlmin:  '<%= htmlmin.dist %>',

          url:    function(url) { return url.replace('.html', ''); },

          module: 'mpoApp'

          usemin: 'scripts\\scripts.js'

        }

      }

    },

Error:

Running "uglify:generated" (uglify) task

[RangeError: Maximum call stack size exceeded]

>> Uglifying source .tmp/concat/scripts/scripts.js failed.

Warning: Uglification failed.

Maximum call stack size exceeded.

 Use --force to continue.


Aborted due to warnings.