Just found this post that was very useful, atleast for me since I had problems launching Opera, while having an error alike but with the newer Opera
/usr/lib/opera/9.0-20060616.6/opera: error while loading shared libraries: libqt-mt.so.3: cannot open shared object file:No such file or directory
The first of all, while you are going to use Opera, you need to download de i386 binary (deb package) and the ia32-libs package that we the users of 64 bits operating systems we always have so I will not explain this step. While you have downloaded the Opera binary, you will need to skip the architecture revision with -if it still at version 9 when you try it 
and of course, doing this at the same folder where this file is
sudo dpkg -i –force-architecture opera_9.*.deb
Opera got installed! But still that error doesn’t let it start so we will download the libqt for i386 arch, extract it and then move it where it would go if we had a i386 system, easy
wget http://ubuntu.mirrors.tds.net/ubuntu/pool/main/q/qt-x11-free/libqt3-mt_3.3.6-1ubuntu3_i386.deb
sudo dpkg -x libqt3-mt_3.3.6-1ubuntu3_i386.deb .
sudo ./usr/lib/libqt* /usr/lib32
And done! we have Opera succefully working on Kubuntu Jaunty Jackalope altought this should work on Ubuntu! Have fun
