Well the pair of us gave up and left the pub about midnight, without getting much further
I don't really know much about the various Linux packaging systems (I'm a Solaris man!) so it was all a bit of guesswork. The EeePC only has the Asus site in its list of package sources, so it couldn't find the allegro libraries.
Adding in the Debian repository just caused it to complain that it couldn't verify the PGP key of the site and refuse to use it.
We tried downloading the *deb packages manually from the Debian site. This worked for the first allegro library, but the next one just hung the installer - probably because it had dependencies that it didn't know how to fetch.
So getting RPCemu running on a standard EeePC still needs some work