libc5 Compatibility in Red Hat 7?

A curious Anonymous Coward wrote in with this important issue: "RedHat Linux 7.0 does not include libc5 compatibility libraries. Trying to run an old binary (RH4.2 or earlier) generates a "no such file or directory" error. To what extent does Red Hat commit to binary backward compatibility? Is it possible to get libc5-based programs, such as MATLAB, working under RH 7 without recompiling?"