After installing RedHat Linux 7, I began to have a very weird, and quite detrimental problem... Matlab 5.3 will not execute. On running the executables I recieve all kinds of "command not found" messages despite the fact that the file exists. In addition, I'm having the same problem with the Laey package of Fortran 90 compilers. I read your previous message about libc5... however these packages run fine under RedHat 6.2 - which as far as I was aware, do not run libc5. As this seems to be a fairly widespread problem affecting all sorts of software your general user may wish to install under RedHat 7 - it seems like you ought to produce a document outlining how to fix this. May I point out that these are the latest releases of this software. And it stands to reason that the new release of Linux ought to support the newest releases of various software packages, or what's the point of upgrading. Let me know if you can help, otherwise I'll be unhappily downgrading to an earlier version of linux.
It is a libc5 issue. Red Hat Linux 6.x used glibc (libc6) by default, but had a compatibility package for old libc5 applications. We've kept a compatibility library for an obsolete and broken libc for about 2 years - that should be enough time for any serious software vendor to update. If you need to use libc5 applications on Red Hat Linux 7, install the libc and ld.so packages from Red Hat Linux 6.x - they'll work, and provide the same backwards compatibility 6.x had.