Compatibility libraries

[Allen, Jack]

        I am trying to compile a program on RedHat AS 4.0 that uses a
3rd party library that was compiled on RedHat AS 2.1. The library has
calls to I think toupper and tolower because I am getting error about
undefined reference __ctype_toupper and __ctype_tolower. In ctypes.h on
RH AS 4.0 I see macros for tolower using __ctype_toupper_loc() and on a
system that has RH 7.3 the macro is defined using __ctype_toupper. I
have another application that required
compat-libstdc++-296.2.96-132.7.2.i386 be installed. It run fine.

        So my question is what CC option do I need to use to use what
ever compatibility libraries? 

        Or do I need to load something else? 

        Or am I just out of luck until the vendor creates a library that
will work on RH AS 4.0? 

Thanks: 
        Jack Allen