> What am I missing?

That's odd as I'm running Arch 32-bit (via VirtualBox on Win7 32-bit) and the ffi-1.0.6 gem builds and installs fine. The only differences between your setup and mine are:

* my Architecture is i686 rather than x86_64
* my ruby version is ruby 1.9.3dev (2011-03-12 trunk 31100) [i686-linux]
* my ruby is installed to /usr/local
* I installed the gem via --user-install and your install needs sudo

Have you tried an uninstall/install cycle rather than update?  Does a --user-install work?

Jon

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