I recommend the following change to SLIME-GLOBAL-VARIABLE-NAME-P so that package-qualified global variables are recognized.
(defun slime-global-variable-name-p (name) "Is NAME a global variable? Globals are recognised purely by *this-naming-convention*." ;(string-match "^\*.*\*$" name) ;; LHQ Sat Nov 27 2004 -- allow optional <package-name>: or <package-name>:: (string-match "^\(.*::?\)?\*.*\*$" name) )