GPL 2.0 with Qt-QCA exception

This library is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2. 

This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this library; see the file COPYING.  If not, write to the Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

As a special exception, the copyright holder(s) give permission to link
  this program with the Qt Library (commercial or non-commercial edition),
  and distribute the resulting executable, without including the source
  code for the Qt library in the source distribution.

  As a special exception, the copyright holder(s) give permission to link
  this program with any other library, and distribute the resulting
  executable, without including the source code for the library in the
  source distribution, provided that the library interfaces with this
  program only via the following plugin interfaces:

    1. The Qt Plugin APIs, only as authored by Trolltech
    2. The QCA Plugin API, only as authored by Justin Karneges