Arabic string not switching to RTL

[Meligy]

This string:

أنا عربي

is in Arabic (it says 'I'm Arab'), and does not seem to work as in:

http://jsbin.com/ifiyit/6/edit

The result of calling JavaScripts native escape() passing the previous string to it was:

%u0623%u0646%u0627%20%u0639%u0631%u0628%u064A

Interestingly, it works on twitter tweet box though.