iOS7 NavTintColor changed to default on click

Hello. Color of navigations buttons were changed from default successfully but in time of click, actually on button up, color of text of button changed to default for a moment. Is that bug?

sample code:

var aboutWin = Ti.UI.createWindow({
    title : 'About',
    backgroundColor : Globals.app_bgColor,
    barColor : Globals.app_uiColor,
    fullscreen: false,
    exitOnClose: false,
    navTintColor: "#fff"
});

Application type: mobile Titanium SDK: 3.1.3.v20130908095038 Platform & version: iOS 7.0, Android x.x, Blackberry x.x, OSX x.x, Windows x, Ubuntu x.x Device: iOS simulator Host Operating System: OSX 10.8.4