I'm using Emacs 22.1 and CVS version of slime.
Strange behaviour: After I open a .lisp file in lisp-mode I start slime. Then the window splits. I get my source file on the top and repl at the bottom.
Now, if I am in the repl, and use the slime selector to my source file, I get "Can't find unshown buffer in lisp-mode"
However, if I close the frame(C-x 5 0) with my source code and then try to use the slime selector to my source file, it works.
Kjeld.