find a newer version of this program? I believe I cam e across this probelm a year or so ago, and found that the version 5 library can be successfully used on an app compiled for 4, so you can *try* symlinking the new lib to the old one...
ln -s libncurses.so.5 libncurses.so.4
assuming they are the correct filenames / directories. then the program should run. but then you appear to be installing from rpm, and what you've done will presumably not be picked up by rpm, so youmay well need to force the rpm install (rpm -Uvh --nodeps blah.rpm).
please bear in mind that this is a cheap dirty hack... but should work. sometimes it's all you can do without downgrading the rest of your system, which you'd never really want to do...