skype: symbol lookup error: skype: undefined symbol:

Question

I am using Ubuntu 12.04 32 bit, skype used to work, but suddenly it stopped. Now when I try to execute through terminal I am getting this error:

skype: symbol lookup error: skype: undefined symbol:

I tried all these solutions:

• "skype: symbol lookup error: skype: undefined symbol"
• Unable to launch Skype in Ubuntu 13.10 64bit - Symbol Lookup Error

but nothing worked. Here's the output of ldd /usr/bin/skype | grep Qt:

libQtDBus.so.4 => /usr/local/qt_lib/libQtDBus.so.4 (0xb581f000)
libQtWebKit.so.4 => /usr/local/qt_lib/libQtWebKit.so.4 (0xb44bf000)
libQtXml.so.4 => /usr/local/qt_lib/libQtXml.so.4 (0xb4474000)
libQtGui.so.4 => /usr/local/qt_lib/libQtGui.so.4 (0xb391b000)
libQtNetwork.so.4 => /usr/local/qt_lib/libQtNetwork.so.4 (0xb37cd000)
libQtCore.so.4 => /usr/local/qt_lib/libQtCore.so.4 (0xb34f9000)

Content of /usr/share/applications/skype.desktop:

[Desktop Entry]
Name=Skype
Comment=Skype Internet Telephony
ec=env PULSE_LATENCY_MSEC=30 LD_LIBRARY_PATH=/usr/local/qt_lib/ skype %U
Icon=skype.png
Terminal=false
Type=Application
Encoding=UTF-8
Categories=Network;Application;
MimeType=x-scheme-handler/skype;
X-KDE-Protocols=skype

EDIT:

Full error:

skype: symbol lookup error: skype: undefined symbol: _ZN19QAbstractProxyModel11setItemDataERK11QModelIndexRK4QMapIi8QVariantE

dpkg --status skype

OUTPUT:

Package: skype
Status: install ok installed
Priority: extra
Section: partner/net
Installed-Size: 61
Maintainer: Steve Langasek <steve.langasek@canonical.com>
Architecture: i386
Version: 4.3.0.37-0ubuntu0.12.04.1
Depends: skype-bin
Conffiles:
 /etc/dbus-1/system.d/skype.conf d09fd2adb2487dbaaeb97c43f6cdc08d obsolete
Description: client for Skype VOIP and instant messaging service
 Skype is software that enables the world's conversations.  Millions of
 individuals and businesses use Skype to make free video and voice calls,
 send instant messages and share files with other Skype users.  Every day,
 people also use Skype to make low-cost calls to landlines and mobiles.
 .
  * Make free Skype-to-Skype calls to anyone else, anywhere in the world.
  * Call to landlines and mobiles at great rates.
  * Group chat with up to 200 people or conference call with up to 25 others.
  * Free to download.
Homepage: http://www.skype.com