I use CMUCL 18e with GNU Emacs 20.7.2 and the latest SLIME CVS sources under Debian Woody. If I evaluate this form in *slime-repl*:
(mp::startup-idle-and-top-level-loops)
the cursor advances to []:
CL-USER> (mp::startup-idle-and-top-level-loops) []
and *slime-repl* blocks, i.e it no longer accepts input. If I press ENTER in *slime-repl*, I get this message in the minibuffer:
Lisp is not ready for requests from REPL
Only *inferior-lisp* remains active.
Paolo