When you create a new MVC 4 Web Application jQuery scripts are included namely jquery-1.7.1.js and jquery.unobstrusive-ajax.js. Now when you bring up the nuget package manager you are encouraged to update the jQuery library to 1.9.* version but if you do this on pages that access the jquery.unobstrusive-ajax.js library you get a reun time error complaining that the .live() functionof the jquery object is unknown on account that it has been decrecated and removed in the laters version and should be replace with the .on() function.
The problem is that the Microsoft based libraries like jquery.unobstrusive-ajax.js have the older deprecated .live() functions in them.
Please correct this in the relevant Microsoft maintained js libraries; perhaps in the 2012.2 update pending for visual studio 2012.