QML Drag and drop does not work in Ubuntu 12.04/14.04

I tried running the externaldraganddrop example in Ubuntu 12.04 and 14.04 with Qt 5.3.1, but the example does not work correct for application internal drags. The first time dragging works, but in the second dragging in a row it does not.

If user clicks (inside application or switches to other application), then dragging works again for one time.

I noticed that mouseArea's drag.active property does not change to false after dragging has been completed. It is set to false only after clicking after the dragging.

In Mac externaldraganddrop example is working just fine.