When I want to install libqtcore4 or libqtgui4 or even libqt4-xml I got this text
maryam@maryam-MM061:~$ sudo apt-get install libqtcore4
[sudo] password for maryam:
Reading package lists... Done
Building dependency tree
Reading state information... Done
libqtcore4 is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 428 not upgraded.
I work with ubuntu 12.10 Thanks