diff --git a/libsrc/c128/mou/c128-1351.s b/libsrc/c128/mou/c128-1351.s
index e55c1d01b..89a32bbd5 100644
--- a/libsrc/c128/mou/c128-1351.s
+++ b/libsrc/c128/mou/c128-1351.s
@@ -3,7 +3,8 @@
 ; the Commodore 1351 mouse users guide.
 ;
 ; 2009-09-26, Ullrich von Bassewitz
-; 2014-03-17, Greg King
+; 2014-04-26, Christian Groessler
+; 2014-04-30, Greg King
 ;
 
         .include        "zeropage.inc"
@@ -12,8 +13,6 @@
 
         .macpack        generic
 
-IRQInd  = $2FD
-
 ; ------------------------------------------------------------------------
 ; Header. Includes jump table
 
@@ -28,8 +27,7 @@ HEADER:
 
 ; Library reference
 
-libref:
-        .addr   $0000
+libref: .addr   $0000
 
 ; Jump table
 
@@ -210,7 +208,7 @@ UNINSTALL:
         sta     IRQInd+1
         lda     old_irq+1
         sta     IRQInd+2
-        cli
+        ;cli
 
         jsr     HIDE                    ; Hide cursor on exit
         lda     INIT_save
@@ -351,7 +349,7 @@ INFO:   jsr     POS
 
 ; Fill in the button state
 
-        jsr     BUTTONS                 ; Will not touch ptr1
+        lda     Buttons
         ldy     #MOUSE_INFO::BUTTONS
         sta     (ptr1),y
 
@@ -363,7 +361,7 @@ INFO:   jsr     POS
 ; Must return an error code in a/x.
 ;
 
-IOCTL:  lda     #<MOUSE_ERR_INV_IOCTL     ; We don't support ioclts for now
+IOCTL:  lda     #<MOUSE_ERR_INV_IOCTL     ; We don't support ioctls, for now
         ldx     #>MOUSE_ERR_INV_IOCTL
         rts
 
diff --git a/libsrc/c128/mou/c128-joy.s b/libsrc/c128/mou/c128-joy.s
index c1dc2e019..2426ebd69 100644
--- a/libsrc/c128/mou/c128-joy.s
+++ b/libsrc/c128/mou/c128-joy.s
@@ -2,7 +2,8 @@
 ; Driver for a "joystick mouse".
 ;
 ; 2009-09-26, Ullrich von Bassewitz
-; 2014-03-17, Greg King
+; 2014-04-26, Christian Groessler
+; 2014-05-01, Greg King
 ;
 
         .include        "zeropage.inc"
@@ -11,8 +12,6 @@
 
         .macpack        generic
 
-IRQInd  = $2FD
-
 ; ------------------------------------------------------------------------
 ; Header. Includes jump table
 
@@ -27,8 +26,7 @@ HEADER:
 
 ; Library reference
 
-libref:
-        .addr   $0000
+libref: .addr   $0000
 
 ; Jump table
 
@@ -91,10 +89,6 @@ Buttons:        .res    1               ; Button mask
 
 INIT_save:      .res    1
 
-; Temporary value used in the int handler
-
-Temp:           .res    1
-
 ; Keyboard buffer fill level at start of interrupt
 
 old_key_count:  .res    1
@@ -215,7 +209,7 @@ UNINSTALL:
         sta     IRQInd+1
         lda     old_irq+1
         sta     IRQInd+2
-        cli
+        ;cli
 
         jsr     HIDE                    ; Hide cursor on exit
         lda     INIT_save
@@ -318,6 +312,7 @@ MOVE:   sei                             ; No interrupts
 BUTTONS:
         lda     Buttons
         ldx     #$00
+        and     #MOUSE_BTN_LEFT         ; Left button -- same as JOY::FIRE
         rts
 
 ;----------------------------------------------------------------------------
@@ -356,7 +351,7 @@ INFO:   jsr     POS
 
 ; Fill in the button state
 
-        lda     Buttons
+        jsr     BUTTONS
         ldy     #MOUSE_INFO::BUTTONS
         sta     (ptr1),y
 
@@ -368,7 +363,7 @@ INFO:   jsr     POS
 ; Must return an error code in a/x.
 ;
 
-IOCTL:  lda     #<MOUSE_ERR_INV_IOCTL     ; We don't support ioclts for now
+IOCTL:  lda     #<MOUSE_ERR_INV_IOCTL     ; We don't support ioctls for now
         ldx     #>MOUSE_ERR_INV_IOCTL
         rts
 
@@ -387,19 +382,10 @@ IRQ:    jsr     CPREP
         lda     CIA1_PRB                ; Read joystick #0
         and     #$1F
         eor     #$1F                    ; Make all bits active high
-        sta     Temp
-
-; Check for a pressed button and place the result into Buttons
-
-        ldx     #$00                    ; Assume no button pressed
-        and     #JOY::FIRE              ; Check fire button
-        beq     @L0                     ; Jump if not pressed
-        ldx     #MOUSE_BTN_LEFT         ; Left (only) button is pressed
-@L0:    stx     Buttons
+        sta     Buttons
 
 ; Check left/right
 
-        lda     Temp                    ; Read joystick #0
         and     #(JOY::LEFT | JOY::RIGHT)
         beq     @SkipX                  ;
 
@@ -447,7 +433,7 @@ IRQ:    jsr     CPREP
 
 ; Calculate the Y movement vector
 
-@SkipX: lda     Temp                    ; Read joystick #0
+@SkipX: lda     Buttons                 ; Read joystick #0
         and     #(JOY::UP | JOY::DOWN)  ; Check up/down
         beq     @SkipY                  ;
 
@@ -499,5 +485,5 @@ IRQ:    jsr     CPREP
         clc                             ; Interrupt not "handled"
         rts
 
-.define  OLD_BUTTONS Temp               ; tells callback.inc where the old port status is stored
+.define OLD_BUTTONS Buttons             ; tells callback.inc where the old port status is stored
 .include "callback.inc"
diff --git a/libsrc/c128/mou/callback.inc b/libsrc/c128/mou/callback.inc
index ea64b8913..9f1d749a7 100644
--- a/libsrc/c128/mou/callback.inc
+++ b/libsrc/c128/mou/callback.inc
@@ -4,7 +4,7 @@
 ;
 ; Christian Groessler, 24.04.2014
 ;
-; Check if there was joystick activity before and/or after the ROM handler.
+; Check if there was button/joystick activity before and/or after the ROM handler.
 ; If there was activity, discard the key presses since they are most
 ; probably "phantom" key presses.
 
diff --git a/libsrc/c128/mouseref.s b/libsrc/c128/mouseref.s
index 630ff573f..243eda804 100644
--- a/libsrc/c128/mouseref.s
+++ b/libsrc/c128/mouseref.s
@@ -1,7 +1,11 @@
 ;
 ; Pointer for library references by device drivers.
 ;
+; Helper-routines for the interrupt handler that rejects bogus keypresses
+; that are caused by mouse-like devices.
+;
 ; 2013-07-25, Greg King
+; 2014-04-26, Christian Groessler
 ;
 
         .include        "c128.inc"
@@ -23,6 +27,7 @@ mouse_libref:                   ; generic label for mouse-kernel
 ;
 _pen_adjuster:
         .addr   $0000
+
         .addr   IRQStub2
 callback:                       ; callback into mouse driver after ROM IRQ handler has been run
         .addr   $0000           ; (filled in by mouse driver)
@@ -83,7 +88,7 @@ IRQStub2:
         rts                     ; jump to callback routine
 
 @IRQCont2:
-        
+
         ; return from interrupt
         ; We could just jump to $FF33, but since I don't know whether this address is valid in all
         ; ROM versions, duplicate that code here.