diff --git a/src/macosx/native/sun/osxapp/QueuingApplicationDelegate.m b/src/macosx/native/sun/osxapp/QueuingApplicationDelegate.m
index 5b71d8ab96c91ff1a20bf33bbf4e94115b75f423..736155fdc0121055233965cd3d116355404c40e0 100644
--- a/src/macosx/native/sun/osxapp/QueuingApplicationDelegate.m
+++ b/src/macosx/native/sun/osxapp/QueuingApplicationDelegate.m
@@ -110,8 +110,14 @@
 
 - (void)_handleOpenURLEvent:(NSAppleEventDescriptor *)openURLEvent withReplyEvent:(NSAppleEventDescriptor *)replyEvent
 {
+    // Make an explicit copy of the passed events as they may be invalidated by the time they're processed
+    NSAppleEventDescriptor *openURLEventCopy = [openURLEvent copy];
+    NSAppleEventDescriptor *replyEventCopy = [replyEvent copy];
+
     [self.queue addObject:[^(){
-        [self.realDelegate _handleOpenURLEvent:openURLEvent withReplyEvent:replyEvent];
+        [self.realDelegate _handleOpenURLEvent:openURLEventCopy withReplyEvent:replyEventCopy];
+        [openURLEventCopy release];
+        [replyEventCopy release];
     } copy]];
 }