Re: "Yup. It was an absolute scandal that Solaris binaries wouldn't run on HPUX."
No, it's an absolute scandal you could not run the same binaries on different releases of the same distro of Linux... because breaking changes in libraries didn't allow that.
LD_LIBRARY_PATH is your friend. Now, this works on all ELF platforms, so Linux, as well as a bunch of UNIX systems, including the BSD's, Solaris and HP-UX* on iTanic .
No such thing as DLL hell on *NIX.
HP-UX has readelf: http://www.polarhome.com/service/man/?qf=readelf&tf=2&of=HP-UX&sf=1