Quoting: "The development machine is an Intel Core2 Quad and the clean machine is a Pentium 4 Dual. I assume g++ defaults to using a common subset of x86 instructions and that the processor difference is not my problem."
I do think that this is a problem.. Try either compiling specifically for that machine or re-compile on the clean-machine, or get two identical machines. - These are my 0.02$.
Also, it looks like you're dying on the loading of the ld-linux.so. Perhaps the linux versions differ?