diff --git a/include/mouse.h b/include/mouse.h
index 1851f5cf..4407b04c 100644
--- a/include/mouse.h
+++ b/include/mouse.h
@@ -16,9 +16,16 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
+/* $Id: mouse.h,v 1.6 2004-03-14 13:39:45 qbix79 Exp $ */
+
+#ifndef _MOUSE_H_
+#define _MOUSE_H_
+
 void Mouse_ShowCursor(void);
 void Mouse_HideCursor(void);
 
+void Mouse_SetPS2State(bool use);
+void Mouse_ChangePS2Callback(Bit16u pseg, Bit16u pofs);
 
 void Mouse_CursorMoved(float x,float y);
 void Mouse_CursorSet(float x,float y);
@@ -28,3 +35,5 @@ void Mouse_ButtonReleased(Bit8u button);
 void Mouse_AutoLock(bool enable);
 void Mouse_NewVideoMode(void);
 
+#endif
+
diff --git a/src/ints/bios.cpp b/src/ints/bios.cpp
index 65e5ecc6..4c6e2137 100644
--- a/src/ints/bios.cpp
+++ b/src/ints/bios.cpp
@@ -16,7 +16,7 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
-/* $Id: bios.cpp,v 1.29 2004-02-29 21:55:49 harekiet Exp $ */
+/* $Id: bios.cpp,v 1.30 2004-03-14 13:39:45 qbix79 Exp $ */
 
 #include <time.h>
 #include "dosbox.h"
@@ -29,6 +29,7 @@
 #include "pic.h"
 #include "joystick.h"
 #include "dos_inc.h"
+#include "mouse.h"
 
 static Bitu call_int1a,call_int11,call_int8,call_int17,call_int12,call_int15,call_int1c;
 static Bitu call_int1,call_int70;
@@ -303,12 +304,50 @@ static Bitu INT15_Handler(void) {
         CALLBACK_SCF(true);
         break;
 	case 0xc2:	/* BIOS PS2 Pointing Device Support */
-	case 0xc4:	/* BIOS POS Programma option Select */
-		/* 
-			Damn programs should use the mouse drivers 
-			So let's fail these calls 
-		*/
-		LOG(LOG_BIOS,LOG_NORMAL)("INT15:Function %X called,bios mouse not supported",reg_ah);
+		switch (reg_al) {
+		case 0x00:		// enable/disable
+			if (reg_bh==0) {	// disable
+				Mouse_SetPS2State(false);
+				reg_ah=0;
+				CALLBACK_SCF(false);
+			} else if (reg_bh==0x01) {	//enable
+				Mouse_SetPS2State(true);
+				reg_ah=0;
+				CALLBACK_SCF(false);
+			} else CALLBACK_SCF(true);
+			break;
+		case 0x01:		// reset
+			reg_bx=0x00aa;	// mouse
+			CALLBACK_SCF(false);
+			break;
+		case 0x02:		// set sampling rate
+			CALLBACK_SCF(false);
+			break;
+		case 0x03:		// set resolution
+			CALLBACK_SCF(false);
+			break;
+		case 0x04:		// get type
+			reg_bh=0;	// ID
+			CALLBACK_SCF(false);
+			break;
+		case 0x05:		// initialize
+			CALLBACK_SCF(false);
+			break;
+		case 0x06:		// extended commands
+			if ((reg_bh==0x01) || (reg_bh==0x02)) CALLBACK_SCF(false);
+			else CALLBACK_SCF(true);
+			break;
+		case 0x07:		// set callback
+			Mouse_ChangePS2Callback(SegValue(es),reg_bx);
+			CALLBACK_SCF(false);
+			break;
+		default:
+			CALLBACK_SCF(true);
+			break;
+		}
+		break;
+	case 0xc4:	/* BIOS POS Programm option Select */
+		LOG(LOG_BIOS,LOG_NORMAL)("INT15:Function %X called, bios mouse not supported",reg_ah);
 		CALLBACK_SCF(true);
 		break;
 	default:
@@ -398,19 +437,20 @@ void BIOS_Init(Section* sec) {
 	/* Setup equipment list */
 	Bitu config=0x4400;						//1 Floppy, 2 serial and 1 parrallel
 #if (C_FPU)
-	config|=0x2;
+	config|=0x2;					//FPU
 #endif
 	switch (machine) {
 	case MCH_HERC:
 		config|=0x30;						//Startup monochrome
 		break;
 	case MCH_CGA:	case MCH_TANDY:
-		config|=0x20;						//STartup 80x25 color
+		config|=0x20;				//Startup 80x25 color
 		break;
 	default:
 		config|=0;							//EGA VGA
 		break;
 	}
+	config |= 0x04;					// PS2 mouse
 	mem_writew(BIOS_CONFIGURATION,config);
 	/* Setup extended memory size */
 	IO_Write(0x70,0x30);
diff --git a/src/ints/mouse.cpp b/src/ints/mouse.cpp
index b5eea37d..d4ef2b09 100644
--- a/src/ints/mouse.cpp
+++ b/src/ints/mouse.cpp
@@ -16,7 +16,7 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
-/* $Id: mouse.cpp,v 1.32 2004-02-29 22:22:56 harekiet Exp $ */
+/* $Id: mouse.cpp,v 1.33 2004-03-14 13:39:45 qbix79 Exp $ */
 
 #include <string.h>
 #include "dosbox.h"
@@ -28,9 +28,71 @@
 #include "inout.h"
 #include "int10.h"
 #include "bios.h"
+#include "cpu.h"
 
 static Bitu call_int33,call_int74;
 
+static Bit16u ps2cbseg, ps2cbofs;
+static bool useps2callback;
+static Bit16u call_ps2;
+static RealPt ps2_callback;
+static Bit16s oldmouseX, oldmouseY;
+
+void Mouse_SetPS2State(bool use) {
+	if ((SegValue(es)!=0) && (reg_bx!=0)) useps2callback = use;
+	else useps2callback = false;
+	Mouse_AutoLock(useps2callback);
+}
+
+void Mouse_ChangePS2Callback(Bit16u pseg, Bit16u pofs) {
+	if ((pseg==0) && (pofs==0)) useps2callback = false;
+	else useps2callback = true;
+	ps2cbseg = pseg;
+	ps2cbofs = pofs;
+	Mouse_AutoLock(useps2callback);
+}
+
+void DoPS2Callback(Bit16u data, Bit16s mouseX, Bit16s mouseY) {
+	if (useps2callback) {
+		Bit16u mdat = (data & 0x03) | 0x08;
+		Bit16s xdiff = mouseX-oldmouseX;
+		Bit16s ydiff = oldmouseY-mouseY;
+		oldmouseX = mouseX;
+		oldmouseY = mouseY;
+
+		if ((xdiff>0xff) || (xdiff<-0xff)) mdat |= 0x40;		// x overflow
+		if ((ydiff>0xff) || (ydiff<-0xff)) mdat |= 0x80;		// y overflow
+
+		xdiff %= 256;
+		ydiff %= 256;
+
+		if (xdiff<0) {
+			xdiff = (0x100+xdiff);
+			mdat |= 0x10;
+		}
+		if (ydiff<0) {
+			ydiff = (0x100+ydiff);
+			mdat |= 0x20;
+		}
+
+		CPU_Push16((Bit16u)mdat); 
+		CPU_Push16((Bit16u)(xdiff % 256)); 
+		CPU_Push16((Bit16u)(ydiff % 256)); 
+		CPU_Push16((Bit16u)0); 
+
+		CPU_Push16(RealSeg(ps2_callback));
+		CPU_Push16(RealOff(ps2_callback));
+		SegSet16(cs, ps2cbseg);
+		reg_ip = ps2cbofs;
+	}
+}
+
+Bitu PS2_Handler(void) {
+	reg_sp += 8;	// remove the 4 words
+	return CBRET_NONE;
+}
+
+
 // forward
 void WriteMouseIntVector(void);
 
@@ -352,11 +414,16 @@ void Mouse_CursorMoved(float x,float y) {
 	mouse.mickey_y += dy;
 
 	mouse.x += dx;
-	if (mouse.x>mouse.max_x) mouse.x=mouse.max_x;
-	if (mouse.x<mouse.min_x) mouse.x=mouse.min_x;
 	mouse.y += dy;
-	if (mouse.y>mouse.max_y) mouse.y=mouse.max_y;
-	if (mouse.y<mouse.min_y) mouse.y=mouse.min_y;
+	
+	/* ignore constraints if using PS2 mouse callback in the bios */
+	if (!useps2callback) {		
+		if (mouse.x > mouse.max_x) mouse.x = mouse.max_x;
+		if (mouse.x < mouse.min_x) mouse.x = mouse.min_x;
+		if (mouse.y > mouse.max_y) mouse.y = mouse.max_y;
+		if (mouse.y < mouse.min_y) mouse.y = mouse.min_y;
+	}
+
 	Mouse_AddEvent(MOUSE_MOVED);
 	DrawCursor();
 }
@@ -762,6 +829,7 @@ static Bitu INT74_Handler(void) {
 			SegSet16(ds,oldds); SegSet16(es,oldes); SegSet16(ss,oldss); // Save segments
 
 		}
+		DoPS2Callback(mouse.event_queue[mouse.events].buttons, POS_X, POS_Y);
 	}
 	IO_Write(0xa0,0x20);
 	IO_Write(0x20,0x20);
@@ -783,7 +851,7 @@ void CreateMouseCallback(void)
 {
 	// Create callback
 	call_int33=CALLBACK_Allocate();
-	CALLBACK_Setup(call_int33,&INT33_Handler,CB_IRET);
+	CALLBACK_Setup(call_int33,&INT33_Handler,CB_IRET,"Mouse");
 	// Create a mouse vector with weird address 
 	// for strange mouse detection routines in Sim City & Wasteland
 	Bit16u ofs = call_int33<<4;
@@ -809,6 +877,12 @@ void MOUSE_Init(Section* sec) {
 		real_writed(0,((0x8+MOUSE_IRQ)<<2),CALLBACK_RealPointer(call_int74));
 	}
 
+	useps2callback = false;
+
+ 	call_ps2=CALLBACK_Allocate();
+	CALLBACK_Setup(call_ps2,&PS2_Handler,CB_IRET,"ps2 bios callback");
+	ps2_callback=CALLBACK_RealPointer(call_ps2);
+
 	memset(&mouse,0,sizeof(mouse));
 	mouse_reset_hardware();
 	mouse_reset();