Not to get new data from server with Ember.js

I has a site based on Ember.js. This site has a textarea where models' field message is set. When user changes this field I make model.save(). Everything is ok but one thing: if I write something while save API request is not finished, text will be flushed to the version been saved to server. How to explain to Ember that I want to use client version of this field, not server version? Sorry for my english :(