How To Get Around FacesContext Being Null In Seperate Servlet - JSF

Question

I am trying to internationalize my web application, so I am using a ResourceBundle and dynamically changing the locale using:

FacesContext.getCurrentInstance()
                .getViewRoot().setLocale(locale);

Which worked fine at first. But I am trying to use an AJAX call to update the page, and the program uses a third party servlet to handle the AJAX calls. So now when my bean gets called, it keeps getting a null exception (since I am not in the FacesServlet, I'm in some other servlet).

The code to call the ajax looks like

<revit:button id="ajaxMe" type="button" 
  onClick="primeAjaxCall();localeCodeChanged();">Select Language</revit:button>
    <revit:ajax method="#{stringbean.localeCodeChanged}"
     call="localeCodeChanged" callback="ajaxCallback" postData="parameter" />

The managed bean code:

public AJAXResponse localeCodeChanged(Map<String, String[]> parameterMap, Map<String, String> headers)
{
    // read in the parameters to get the locale

    // how can I effectively call this without null pointer?
     FacesContext.getCurrentInstance().getViewRoot().setLocale(locale);
}

Any ideas?