Difference between org/springframework/web/servlet/ModelAndView class and org/springframework/web/portlet/ModelAndView

I have just answered the below question which revolves around this posted question.

spring mvc InternalResourceViewResolver doesnt get prefix

Can someone out there tell the difference between the classes

org/springframework/web/servlet/ModelAndView and org/springframework/web/portlet/ModelAndView

I see almost similar API docs for both

http://ift.tt/1Hg6hwT

and

http://ift.tt/1Hg6hwV

where both have the constructor

ModelAndView(String viewName)
Convenient constructor when there is no model data to expose.

and yet the later doesn't work in resolving the view?