diff --git a/src/java/com/samskivert/util/Invoker.java b/src/java/com/samskivert/util/Invoker.java
index 8d7a5a08..e0e31f03 100644
--- a/src/java/com/samskivert/util/Invoker.java
+++ b/src/java/com/samskivert/util/Invoker.java
@@ -144,7 +144,7 @@ public class Invoker extends LoopingThread
      */
     public void postUnit (Unit unit)
     {
-        if (!shutdownRequested()) {
+        if (shutdownRequested()) {
             throw new IllegalStateException("Cannot post units to shutdown invoker.");
         }
         // note the time