Can't help with 1 and 3 but for 2:
I think this message means that you did not install the needed development tools. Don't know about RH Enterprise, but on Rh9 install you get an explicit option to install development stuff (compilers and C-libraries). You seem to be missing the C libraries, and this is why AIM won't compile. Are you sure you checked the
relevant section during the installation process of RH Enterprise edition that allows development? If it is there, make sure you check this and install both libc and the C++ libraries and all relevant headers, as well as compilers (gcc). You might be able to install this after the "actual" initial installation but I don't know how. I once ran into this with Rh9 and had to reformat and re-install to get development working on my system.
You need to tell your installation process that you want to do development with your install - if you did not, you won't be able to compile anything. (I think)