You need libncurses.so.4.
Easysoft build unixODBC Driver Manager with readline support using ncurses4 in an attempt to make it compatible with as many Linux distributions as possible. Some new distributions do not install compatibility libraries by default, and only include the latest library versions.
We have had this reported for Red Hat. Install ncurses4-5.0-9i386 from your Red Hat distribution.
Alternatively, build unixODBC yourself. Get the ncurses4 source distribution and build it yourself.