init-alert.el

(require 'alert)

(setq alert-default-style 'growl)
(alert-add-rule :status   '(buried visible idle)
                :severity '(moderate high urgent)
                :mode     'erc-mode
                :predicate
                #'(lambda (info)
                    (string-match (concat "\\`[^&].*@BitlBee\\'")
                                  (erc-format-target-and/or-network)))
                :persistent
                #'(lambda (info)
                    ;; If the buffer is buried, or the user has been
                    ;; idle for `alert-reveal-idle-time' seconds,
                    ;; make this alert persistent.  Normally, alerts
                    ;; become persistent after
                    ;; `alert-persist-idle-time' seconds.
                    (memq (plist-get info :status) '(buried idle)))
                :style 'fringe
                :continue t)

(provide 'init-alert)