diff --git a/libsrc/c128/mou/c128-pot.s b/libsrc/c128/mou/c128-pot.s
index 4e549cc6d..f760d6b62 100644
--- a/libsrc/c128/mou/c128-pot.s
+++ b/libsrc/c128/mou/c128-pot.s
@@ -3,7 +3,7 @@
 ;
 ; 2006-08-20, Stefan Haubenthal
 ; 2009-09-26, Ullrich von Bassewitz
-; 2014-03-17, Greg King
+; 2014-05-05, Greg King
 ;
 
         .include        "zeropage.inc"
@@ -43,6 +43,10 @@ HEADER:
         .addr   IOCTL
         .addr   IRQ
 
+; Mouse driver flags
+
+        .byte   MOUSE_FLAG_LATE_IRQ
+
 ; Callback table, set by the kernel before INSTALL is called
 
 CHIDE:  jmp     $0000                   ; Hide the cursor
diff --git a/libsrc/c64/mou/c64-pot.s b/libsrc/c64/mou/c64-pot.s
index 17308f6ac..1ebbd26e2 100644
--- a/libsrc/c64/mou/c64-pot.s
+++ b/libsrc/c64/mou/c64-pot.s
@@ -3,7 +3,7 @@
 ;
 ; 2006-08-20, Stefan Haubenthal
 ; 2009-09-26, Ullrich von Bassewitz
-; 2014-03-17, Greg King
+; 2014-05-05, Greg King
 ;
 
         .include        "zeropage.inc"
@@ -43,6 +43,10 @@ HEADER:
         .addr   IOCTL
         .addr   IRQ
 
+; Mouse driver flags
+
+        .byte   MOUSE_FLAG_LATE_IRQ
+
 ; Callback table, set by the kernel before INSTALL is called
 
 CHIDE:  jmp     $0000                   ; Hide the cursor