diff --git a/libsrc/mouse/Makefile b/libsrc/mouse/Makefile
index a2138d04a..a48ebf4ac 100644
--- a/libsrc/mouse/Makefile
+++ b/libsrc/mouse/Makefile
@@ -20,6 +20,7 @@
 C_OBJS =        mouse_load.o
 
 S_OBJS =        mouse-kernel.o  \
+                mouse_box.o     \
                 mouse_hide.o    \
                 mouse_info.o    \
                 mouse_ioctl.o   \
diff --git a/libsrc/mouse/mouse_box.s b/libsrc/mouse/mouse_box.s
new file mode 100644
index 000000000..e94feda4c
--- /dev/null
+++ b/libsrc/mouse/mouse_box.s
@@ -0,0 +1,33 @@
+;
+; Ullrich von Bassewitz, 2004-03-23
+;
+; void __fastcall__ mouse_box (int minx, int miny, int maxx, int maxy);
+; /* Set the bounding box for the mouse pointer movement. The mouse X and Y
+;  * coordinates will never go outside the given box.
+;  * NOTE: The function does *not* check if the mouse is currently inside the
+;  * given margins. The proper way to use this function therefore is:
+;  *
+;  * 	- Hide the mouse
+;  * 	- Set the bounding box
+;  * 	- Place the mouse at the desired position
+;  * 	- Show the mouse again.
+;  *
+;  * NOTE2: When setting the box to something that is larger than the actual
+;  * screen, the positioning of the mouse cursor can fail. If such margins
+;  * are really what you want, you have to use your own cursor routines.
+;  */
+;
+
+        .import         incsp6
+
+        .include        "mouse-kernel.inc"
+
+.proc   _mouse_box
+
+        jsr     mouse_box               ; Call the driver
+        jmp     incsp6                  ; Cleanup the stack
+
+.endproc
+
+
+