diff --git a/ChangeLog b/ChangeLog
index 2512510..e618eb7 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -4,6 +4,11 @@
 <standard changelog date stamp>
 	* <changes go here...>
 
+*******************************************************************************
+2009-05-04  Duane Rettig  <duane@franz.com>
+
+	* defsystem.cl: bug18431: Fix compiler-switch for 8.2
+
 *******************************************************************************
 merge from acl81 to master, changes from
 	2007-09-07  Duane Rettig  <duane@franz.com>
diff --git a/defsystem.cl b/defsystem.cl
index 09b4d6f..4028e85 100644
--- a/defsystem.cl
+++ b/defsystem.cl
@@ -150,12 +150,12 @@
 ;; prepared for possible deadlock, since no interrupts will be recognized
 ;; while reading from the X socket if the scheduler is not running.
 ;;
-#+excl
+;; [bug18431]:
 (setq compiler::generate-interrupt-checks-switch
-      (compile nil
-	       '(lambda (safety size speed &optional debug)
-		  (declare (ignore size debug))
-		  (or (< speed 3) (> safety 0)))))
+  (compile nil
+	   '(lambda (safety size speed &optional debug compilation-speed)
+	     (declare (ignore size debug compilation-speed))
+	     (or (< speed 3) (> safety 0)))))
 
 
 ;;; Allegro