Issue with with 'use strict' and underscore.js

Issue with with 'use strict' and underscore.js

I've written an app using Yeoman and backbone.js. At the top of every js
file I have specified 'use strict'; and when I run my grunt tasks jshint
does not encounter any errors.
I am able to build my app with grunt without issue however when I try to
run the uglified js I get the following error:
Uncaught SyntaxError: Strict mode code may not include a with statement
I've searched the code base and the only things using a with statement is
underscore.
I'm new to strict mode so I'm not sure how I can resolve this issue. Can I
not use strict mode anywhere that I use an underscorejs function?
Thanks.