It seems that the webserver links to an absolute path during compile time which may not present after make install.
I've installed julia to /usr/share/julia and deleted the compilation directory. Running launch-julia-webserver gives me:
Connect to http://localhost:2000/ for the web REPL.
2012-05-13 00:51:19: (plugin.c.169) dlopen() failed for: /home/user/Downloads/archlinux-JuliaLang/src/julia-build/usr/lib/mod_indexfile.so /home/user/Downloads/archlinux-JuliaLang/src/julia-build/usr/lib/mod_indexfile.so: cannot open shared object file: No such file or directory
2012-05-13 00:51:19: (server.c.657) loading plugins finally failed
SCGI server started on port 2001.
0 open sessions.
This seems like an issue with the lighttpd build.
I really don't know what to do about this. :-(
Thanks, maybe I can find a way to compile lighthttp with the correct path. I'll close the issue since it's more or less a packaging-issue.
The right thing might be to USE_SYSTEM_LIGHTTPD if available.
Just in case anyone finds this, I found it was looking for the lighttpd plugins in /lib, while on my machine (Arch linux) they were in /lib/lighttpd. I assume this is true of all Arch users so I could patch this. I'm forking now to fix it.