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Afterwards I did a fresh installation on the AMD64 iepm-raptor1 machine again. I compared the makefiles generated by the configure script for the RRDs package on both the pinger and iepm-raptor1 machines and discovered that the problem was that while the script was using 32-bit AFS perl to compile the module, it was using 64-bit gcc to use the Perl Interpretor to create to RRcreate the dynamic link libraries. This was why the 64-bit file was RRDs.so file was being generated despite using 32-bit afs perl to compile it.
Having figured this out I tried to figure out in the configure script where the gcc path was being set. Turns out the configure script takes the perl path from the PERL environment variable and the gcc path from the PERLCC environment variable. With this information I tried setting the perl path and the gcc path to various combinations of 32-bit and 64-bit binaries located in the /afs/slac/package/perl and /afs/slac/package/gcc locations.
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