I got a new USB modem from my operator and it contained driver for linux so I installed it and now when I try to run it I get the below error

error while loading shared libraries: libqt-mt.so.3: cannot open shared object file: No such file or directory

I searched for that lib and found it in /usr/lib64 and /usr/lib/qt3/lib64

Do I need to install the 32 bit version? how to be sure about that?