The garden uses Debian. And file tells me the luatex binary is actually 32-bit, although I wonder how this can be possible.
Problem is on 64bit gentoo. On a 32bit (at home) it works.
What is your error message exactly?
Commands luatools --ini --compile --verbose cont-en and texmfstart texexec --make --all --luatex do not produce error message at all. But texmfstart texexec --luatex something.tex ends with: This is luaTeX, Version 3.141592-beta-0.11.0-2007082309 (Web2C 7.5.6) luatex: /tmp/luatex-cache/context/2bee42bddafb2afd5c3c1eaea23baaa5/formats/cont-en.fmt: No such file or directory LuaTools | running command: luatex --fmt="/tmp/luatex-cache/context/2bee42bddafb2afd5c3c1eaea23baaa5/formats/cont-en" --lua="/tmp/luatex-cache/context/2bee42bddafb2afd5c3c1eaea23baaa5/formats/cont-en.luc" "something.tex"