diff --git a/lisp/org-agenda.el b/lisp/org-agenda.el
index 991a94a..0d074a7 100644
--- a/lisp/org-agenda.el
+++ b/lisp/org-agenda.el
@@ -7770,11 +7770,12 @@ the resulting entry will not be shown.  When TEXT is empty, switch to
       (insert "\n")
       (require 'diary-lib)
       (let ((calendar-date-display-form
-	     (if (if (boundp 'calendar-date-style)
-		     (eq calendar-date-style 'european)
-		   (with-no-warnings ;; european-calendar-style is obsolete as of version 23.1
-		     (org-bound-and-true-p european-calendar-style))) ; Emacs 22
-		 '(day " " month " " year)
+	     (if (boundp 'calendar-date-style)
+		 (if (eq calendar-date-style 'european)
+		     '(day " " month " " year)
+		   (if (eq calendar-date-style 'iso)
+		       '(year " " month " " day)
+		     '(month " " day " " year)))
 	       '(month " " day " " year))))
 
 	(insert (format "%%%%(diary-anniversary %s) %s"