I wanted to be able to run cmucl and ccl on c-l.net (to run some automated tests).

Cmucl won't run; I think the 32-bit libraries that cmucl needs are missing.  I tried running both 32- and 64-bit ccl, but there's some strange error produced. I can't tell if that's caused by c-l.net or some bug in ccl.

Don't know if this is a goal for c-l.net, but it seems natural that c-l.net should be able to run common lisp implementations. :-)