"set shiftround" doesn't work in Vim?

I'm using MacVim, and when trying to set shiftround in my .vimrc I get the following error:

E518: Unknown option:  shiftround

EDIT: However, when I try to :set shiftround manually within Vim, it works and gives no errors.

Anybody knows what is 开发者_开发知识库causing this? If somebody wants to view my whole .vimrc (perhaps something else I'm not of is the cause of this), please do:

https://github.com/oryband/dotvim/blob/master/vimrc

Using MacVim 7.3, that option works for me: vimrc link. Which version of MacVim are you using? Like michaelmichael asked, what happens if you try :set shiftround within the application?