Keyboard won't show on input focus in webview on Android

The keyboard won't popup when tapping an input field in a webview, which contains a simple login form. It works in the emulator, but not on my device (galaxy s2).

Device: Android

SDK: 3.0.0.GA, Runtime: V8, Studio: 3.0.0.201212131639

The project is based on a single window application, commonjs structure.

code:

var win = Ti.UI.createWindow();
var webview = Ti.UI.createWebView({
  url : 'http://www.domain.com/page.php'
});
win.add(webview);
win.open();

I tried adding softKeyboardOnFocus ( Titanium.UI.Android.SOFT_KEYBOARD_SHOW_ON_FOCUS and Titanium.UI.Android.SOFT_KEYBOARD_DEFAULT_ON_FOCUS ) without any luck. Also, no errors in the console.

Any idea?