I had to change the "push" to a "pushnew" (and add a test) in the following function in hyperspec.el to keep my browser from opening up more than 1 tab for a (common-lisp-hyperspec ...) query. This is from today's cvs pull.
(defun intern-clhs-symbol (string relative-url) (let ((symbol (intern string common-lisp-hyperspec-symbols))) (if (boundp symbol) (pushnew relative-url (symbol-value symbol) :test 'equal) (set symbol (list relative-url)))))