xul textbox autocomplete popup broken

I have a Firefox add on that has a search text box with an auto complete popup, in Firefox 29 and 30 when a user uses the mouse to open the popup list and clicks an entry in the list, the entry gets automatically selects and it appears in the text box. 
The above described behaviour seems broken in Firefox 31, when the user clicks an entry in the list, the selected item does not get selected and does not appear in the text box. 
below is a sample of my code 

{code}
<bindings id="FCTBSearchBindings" 
   xmlns="http://www.mozilla.org/xbl" 
   xmlns:html="http://www.w3.org/1999/xhtml" 
   xmlns:xul="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul" 
   xmlns:xbl="http://www.mozilla.org/xbl"> 
    
        <binding id="FCTB_search"> 
                <content sizetopopup="pref" flex="0"> 
                      <xul:hbox> 
  
                           <xul:textbox 
                                   anonid="fctb_searh_textbox" 
                                  class="fctb_search_textbox" 
                                  type="autocomplete" 
                                  autocompletesearch="fctb-auto-complete" 
                                  autocompletepopup="fctb-search-autocomplete-popup" 
                                  ignoreblurwhilesearching="true" 
                                  completeselectedindex="true" 
                                  flex="1" 
                                  persist="width" 
                                  sizetopopup="no" 
                                  enablehistory="true"                                    
                                  onkeypress="fctb_get_parent(this, 'fctb_search').FCTBCompObj.KeyHandler(event);" 
                                  maxrows="0" 
                                  fcempty="true" 
                                  onblur="fctb_get_parent(this, 'fctb_search').setEmpty(event);fctb_get_parent(this, 'fctb_search').FCTBCompObj.OnBlur(event);" 
                                  xbl:inherits="width,enablehistory,style=textboxstyle" 
                                  maxlength="2000" size="2000"> 
{code}

Thanks in advance