when I start gnome-disk-utility, the top part part of its window is under the top bar of unity

[SteliosSk]

As described, in ubuntu trusty, when I start gnome-disk-utlity, the top part of its window (which has the min-max-close buttons) is under the top bar of unity. Please see picture at https://dl.dropboxusercontent.com/u/19393967/gnome-disk-utility.png

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: gnome-disk-utility 3.10.0-1ubuntu2
ProcVersionSignature: Ubuntu 3.13.0-18.38-generic 3.13.6
Uname: Linux 3.13.0-18-generic x86_64
ApportVersion: 2.13.3-0ubuntu1
Architecture: amd64
CurrentDesktop: Unity
Date: Fri Mar 21 13:24:38 2014
ExecutablePath: /usr/bin/gnome-disks
InstallationDate: Installed on 2014-03-07 (13 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Alpha amd64 (20140307)
ProcEnviron:
 LANGUAGE=el
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=el_GR.UTF-8
 SHELL=/bin/bash
SourcePackage: gnome-disk-utility
UpgradeStatus: No upgrade log present (probably fresh install)