diff --git a/reactos/lib/ppcmmu/devint.s b/reactos/lib/ppcmmu/devint.s
index 77106204334..5ed65b4d501 100644
--- a/reactos/lib/ppcmmu/devint.s
+++ b/reactos/lib/ppcmmu/devint.s
@@ -5,61 +5,60 @@
 mmumain:
         mr 0,1
         lis 1,2
-        subi 1,1,432
-        stw 0,4(1)
-        stw 2,8(1)
-	stw 3,12(1)
-	stw 4,16(1)
-	stw 5,20(1)
-	stw 6,24(1)
-	stw 7,28(1)
-	stw 8,32(1)
-	stw 9,36(1)
-        stw 10,40(1)
-	stw 11,44(1)
-	stw 12,48(1)
-	stw 13,52(1)
-	stw 14,56(1)
-	stw 15,60(1)
-	stw 16,64(1)
-	stw 17,68(1)
-	stw 18,72(1)
-	stw 19,76(1)
-	stw 20,80(1)
-        stw 21,84(1)
-        stw 22,88(1)
-	stw 23,92(1)
-	stw 24,96(1)
-	stw 25,100(1)
-	stw 26,104(1)
-	stw 27,108(1)
-	stw 28,112(1)
-	stw 29,116(1)
-	stw 30,120(1)
-	stw 31,124(1)
-	mflr 0
-	stw 0,384(1)
-	mfmsr 0
-	stw 0,388(1)
-	mfcr 0
-	stw 0,392(1)
-	mflr 0
-	stw 0,396(1)
-	mfctr 0
+        subi 1,1,448
+        stw 0,20(1)
+        stw 2,24(1)
+	stw 3,28(1)
+	stw 4,32(1)
+	stw 5,36(1)
+	stw 6,40(1)
+	stw 7,44(1)
+	stw 8,48(1)
+	stw 9,52(1)
+        stw 10,56(1)
+	stw 11,60(1)
+	stw 12,64(1)
+	stw 13,68(1)
+	stw 14,72(1)
+	stw 15,76(1)
+	stw 16,80(1)
+	stw 17,84(1)
+	stw 18,88(1)
+	stw 19,92(1)
+	stw 20,96(1)
+        stw 21,100(1)
+        stw 22,104(1)
+	stw 23,108(1)
+	stw 24,112(1)
+	stw 25,116(1)
+	stw 26,120(1)
+	stw 27,124(1)
+	stw 28,128(1)
+	stw 29,132(1)
+	stw 30,136(1)
+	stw 31,140(1)
+	mfsrr0 0
 	stw 0,400(1)
-	mfxer 0
+	mfmsr 0
 	stw 0,404(1)
-	xor 0,0,0
+	mfcr 0
 	stw 0,408(1)
-	mfdsisr 0
+	mflr 0
 	stw 0,412(1)
+	mfctr 0
+	stw 0,416(1)
+	mfxer 0
+	stw 0,420(1)
+	/* xor 0,0,0 -- We can omit this since PPC doesn't have MQ */
+	stw 0,424(1)
+	mfdsisr 0
+	stw 0,428(1)
         mfdar 0
-        stw 0,416(1)
-        mr 7,1
+        stw 0,432(1)
+        addi 7,1,16
         lis 8,_mmumain@ha
         addi 8,8,_mmumain@l
         mtctr 8
-        subi 1,1,16
 	bctrl
         addi 1,1,16
 	lwz 2,8(1)
@@ -98,7 +97,9 @@ mmumain:
         mtlr 0
         lwz 0,400(1)
         mtctr 0
+	lwz 0,388(1) /* Copy out new MSR bits if needed */
 	lwz 1,4(1)
+	mtmsr 0
         blr
 
         .globl trap_start
@@ -106,68 +107,67 @@ mmumain:
 trap_start:
         mtsprg1 1
         lis 1,2
-        subi 1,1,432
-        stw 0,0(1)
+        subi 1,1,448
+        stw 0,16(1)
         mfsprg1 0
-        stw 0,4(1)
-        stw 2,8(1)
-	stw 3,12(1)
-	stw 4,16(1)
-	stw 5,20(1)
-	stw 6,24(1)
-	stw 7,28(1)
-	stw 8,32(1)
-	stw 9,36(1)
-        stw 10,40(1)
-	stw 11,44(1)
-	stw 12,48(1)
-	stw 13,52(1)
-	stw 14,56(1)
-	stw 15,60(1)
-	stw 16,64(1)
-	stw 17,68(1)
-	stw 18,72(1)
-	stw 19,76(1)
-	stw 20,80(1)
-        stw 21,84(1)
-        stw 22,88(1)
-	stw 23,92(1)
-	stw 24,96(1)
-	stw 25,100(1)
-	stw 26,104(1)
-	stw 27,108(1)
-	stw 28,112(1)
-	stw 29,116(1)
-	stw 30,120(1)
-	stw 31,124(1)
+        stw 0,20(1)
+        stw 2,24(1)
+	stw 3,28(1)
+	stw 4,32(1)
+	stw 5,36(1)
+	stw 6,40(1)
+	stw 7,44(1)
+	stw 8,48(1)
+	stw 9,52(1)
+        stw 10,56(1)
+	stw 11,60(1)
+	stw 12,64(1)
+	stw 13,68(1)
+	stw 14,72(1)
+	stw 15,76(1)
+	stw 16,80(1)
+	stw 17,84(1)
+	stw 18,88(1)
+	stw 19,92(1)
+	stw 20,96(1)
+        stw 21,100(1)
+        stw 22,104(1)
+	stw 23,108(1)
+	stw 24,112(1)
+	stw 25,116(1)
+	stw 26,120(1)
+	stw 27,124(1)
+	stw 28,128(1)
+	stw 29,132(1)
+	stw 30,136(1)
+	stw 31,140(1)
 	mfsrr0 0
-	stw 0,384(1)
-	mfsrr1 0
-	stw 0,388(1)
-	mfcr 0
-	stw 0,392(1)
-	mflr 0
-	stw 0,396(1)
-	mfctr 0
 	stw 0,400(1)
-	mfxer 0
+	mfsrr1 0
 	stw 0,404(1)
-	xor 0,0,0
+	mfcr 0
 	stw 0,408(1)
-	mfdsisr 0
+	mflr 0
 	stw 0,412(1)
+	mfctr 0
+	stw 0,416(1)
+	mfxer 0
+	stw 0,420(1)
+	/* xor 0,0,0 -- We can omit this since PPC doesn't have MQ */
+	stw 0,424(1)
+	mfdsisr 0
+	stw 0,428(1)
         mfdar 0
-        stw 0,416(1)
+        stw 0,432(1)
         bl 1f
 1:      mflr 5
-        mr 4,1
+        addi 4,1,16
         rlwinm 3,5,24,0xff
         lwz 5,36(5)
         mtctr 5
 	lis 5,trap_finish_start@ha
 	addi 5,5,trap_finish_start@l
 	mtlr 5
-        subi 1,1,16
 	bctr
 trap_end:
 	.space 4
diff --git a/reactos/lib/ppcmmu/gdblib.c b/reactos/lib/ppcmmu/gdblib.c
index 7a2d7189064..5a423db6ceb 100644
--- a/reactos/lib/ppcmmu/gdblib.c
+++ b/reactos/lib/ppcmmu/gdblib.c
@@ -31,6 +31,7 @@
  *
  *  Modified for 386 by Jim Kingdon, Cygnus Support.
  *  Modified for ReactOS by Casper S. Hornstrup <chorns@users.sourceforge.net>
+ *  Modified heavily for PowerPC ReactOS by arty
  *
  *  To enable debugger support, two things need to happen.  One, setting
  *  up a routine so that it is in the exception path, is necessary in order
@@ -127,12 +128,12 @@ int isxdigit(int ch)
         (ch >= '0' && ch <= '9');
 }
 
-void sync() {
+inline void sync() {
     __asm__("eieio\n\t"
 	    "sync");
 }
 
-void send(char *serport, char c) {
+inline void send(char *serport, char c) {
 	/* Wait for Clear to Send */
     while( !(serport[LSR] & 0x20) ) sync();
     
@@ -140,16 +141,22 @@ void send(char *serport, char c) {
     sync();
 }
 
-int rdy(char *serport)
+inline int rdy(char *serport)
 {
     sync();
     return (serport[LSR] & 0x20);
 }
 
-char recv(char *serport) {
+inline int chr(char *serport)
+{
+    sync();
+    return serport[LSR] & 1;
+}
+
+inline char recv(char *serport) {
     char c;
 
-    while( !(serport[LSR] & 1) ) sync();
+    while( !chr(serport) ) sync();
     
     c = serport[RCV];
     sync();
@@ -167,8 +174,6 @@ void setup(char *serport, int baud) {
 	sync();
 	serport[LCR] = 3;
 	sync();
-	serport[IER] = 1;
-	sync();
 }
 
 void SerialSetUp(int deviceType, void *deviceAddr, int baud)
@@ -178,11 +183,11 @@ void SerialSetUp(int deviceType, void *deviceAddr, int baud)
     setup(serport, baud);
 }
 
-extern void SerialInterrupt();
+extern int SerialInterrupt(int signal, ppc_trap_frame_t *tf);
 
-void Wait()
+void IntEnable()
 {
-    while(!Continue) if (rdy(serport)) SerialInterrupt();
+    serport[IER] |= 1;
 }
 
 void SerialWrite(int ch)
@@ -240,22 +245,44 @@ void PacketStart()
 
 void PacketFinish()
 {
-    int i, ch;
+    int i, ch, count = 0;
 
     PacketSent = 0;
     
     do {
-        SerialWrite('$');
-        for (i = 0; i < DataOutAddr; i++)
-        {
-            SerialWrite(DataOutBuffer[i]);
+        if (!count)
+        { 
+            SerialWrite('$');
+            for (i = 0; i < DataOutAddr; i++)
+            {
+                SerialWrite(DataOutBuffer[i]);
+            }
+            SerialWrite('#');
+            SerialWrite(hex[(DataOutCsum >> 4) & 15]);
+            SerialWrite(hex[DataOutCsum & 15]);
         }
-        SerialWrite('#');
-        SerialWrite(hex[(DataOutCsum >> 4) & 15]);
-        SerialWrite(hex[DataOutCsum & 15]);
+        while(count-- != 0)
+        {
+            if (chr(serport))
+            {
+                ch = SerialRead();
+                break;
+            }
+        }
+        
+        switch (ch)
+        {
+        default:
+            break;
 
-        while(!rdy(serport));
-        if (SerialRead() == '+') break;
+        case '-':
+            count = 0;
+            break;
+
+        case '+':
+            PacketSent = 1;
+            break;
+        }
     } while(PacketSent != 1);
 }
 
@@ -293,10 +320,13 @@ void PacketWriteError(int code)
     PacketFinish();
 }
 
+void marker() { }
+
 void GotPacket()
 {
     int i, memaddr, memsize;
-
+    
+    Continue = 0;
     switch (DataInBuffer[DataInAddr++])
     {
     case 'g':
@@ -349,10 +379,16 @@ void GotPacket()
         Continue = 1;
         break;
 
+    case 'S':
+        PacketOk();
+        Continue = 0;
+        break;
+
     case 's':
-        RegisterSaveArea->srr1 |= 16;
+        RegisterSaveArea->srr1 |= 0x400;
         PacketOk();
         Continue = 1;
+        marker();
         break;
 
     case 'q':
@@ -374,59 +410,74 @@ void GotPacket()
     }
 }
 
-void SerialInterrupt()
+int SerialInterrupt(int signal, ppc_trap_frame_t *tf)
 {
-    int ch = SerialRead();
+    int ch;
 
-    if (ch == '+')
+    if (!chr(serport)) return 0;
+
+    Signal = signal;
+    RegisterSaveArea = tf;
+    
+    do 
     {
-        PacketSent = 1;
-    }
-    else if (ch == '-')
-    {
-        PacketSent = -1;
-    }
-    else if (ch == '$')
-    {
-        DataInAddr = 0;
-        ParseState = 0;
-        ComputedCsum = 0;
-        ActualCsum = 0;
-    }
-    else if (ch == '#' && ParseState == 0)
-    {
-        ParseState = 2;
-    }
-    else if (ParseState == 0)
-    {
-        ComputedCsum += ch;
-        DataInBuffer[DataInAddr++] = ch;
-    }
-    else if (ParseState == 2)
-    {
-        ActualCsum = ch;
-        ParseState++;
-    }
-    else if (ParseState == 3)
-    {
-        ActualCsum = hex2int(ch) | (hex2int(ActualCsum) << 4);
-        ComputedCsum &= 255;
-        ParseState = -1;
-        if (ComputedCsum == ActualCsum)
+        ch = SerialRead();
+        
+        if (ch == 3) /* Break in - tehe */
         {
-            ComputedCsum = 0;
-            DataInBuffer[DataInAddr] = 0;
-            DataInAddr = 0;
             Continue = 0;
-            SerialWrite('+');
-            GotPacket();
+            PacketWriteSignal(3);
         }
-        else
+        else if (ch == '-' || ch == '+')
+        {
+            /* Nothing */
+        }
+        else if (ch == '$')
+        {
+            DataInAddr = 0;
+            ParseState = 0;
+            ComputedCsum = 0;
+            ActualCsum = 0;
+        }
+        else if (ch == '#' && ParseState == 0)
+        {
+            ParseState = 2;
+        }
+        else if (ParseState == 0)
+        {
+            ComputedCsum += ch;
+            DataInBuffer[DataInAddr++] = ch;
+        }
+        else if (ParseState == 2)
+        {
+            ActualCsum = ch;
+            ParseState++;
+        }
+        else if (ParseState == 3)
+        {
+            ActualCsum = hex2int(ch) | (hex2int(ActualCsum) << 4);
+            ComputedCsum &= 255;
+            ParseState = -1;
+            if (ComputedCsum == ActualCsum)
+            {
+                ComputedCsum = 0;
+                DataInBuffer[DataInAddr] = 0;
+                DataInAddr = 0;
+                Continue = 0;
+                SerialWrite('+');
+                GotPacket();
+            }
+            else
+                SerialWrite('-');
+        }
+        else if (ParseState == -1)
             SerialWrite('-');
     }
+    while (!Continue);
+    return 1;
 }
 
-void TakeException(int n, int *tf)
+int TakeException(int n, ppc_trap_frame_t *tf)
 {
     Signal = n;
     RegisterSaveArea = tf;
@@ -434,7 +485,8 @@ void TakeException(int n, int *tf)
         PacketWriteSignal(Signal);
     SendSignal = 0;
     Continue = 0;
-    Wait();
+    while(!Continue) SerialInterrupt(n, tf);
+    return 1;
 }
 
 /* EOF */
diff --git a/reactos/lib/ppcmmu/mmuobject.c b/reactos/lib/ppcmmu/mmuobject.c
index 9b5c5d7b41c..cc8ab4c4535 100644
--- a/reactos/lib/ppcmmu/mmuobject.c
+++ b/reactos/lib/ppcmmu/mmuobject.c
@@ -68,7 +68,8 @@ MmuVsidInfo *Segs[16], *VsidHead = 0;
 extern void fmtout(const char *fmt, ...);
 int ptegreload(ppc_trap_frame_t *frame, vaddr_t addr);
 void SerialSetUp(int deviceType, void *deviceAddr, int baud);
-void TakeException(int n, int *tf);
+int SerialInterrupt(int n, ppc_trap_frame_t *tf);
+void TakeException(int n, ppc_trap_frame_t *tf);
 
 int _mmumain(int action, void *arg1, void *arg2, void *arg3, void *tf)
 {
@@ -83,36 +84,42 @@ int _mmumain(int action, void *arg1, void *arg2, void *arg3, void *tf)
 	if(!ptegreload(trap_frame, trap_frame->dar))
 	{
 	    __asm__("mfmsr 3\n\tori 3,3,0x30\n\tmtmsr 3\n\t");
-	    if (!callback[action](action,tf)) hang(action, tf);
+	    if (!callback[action](action,trap_frame)) hang(action, trap_frame);
 	}
 	break;
     case 4:
 	if(!ptegreload(trap_frame, trap_frame->srr0))
 	{
 	    __asm__("mfmsr 3\n\tori 3,3,0x30\n\tmtmsr 3\n\t");
-	    if (!callback[action](action,tf)) hang(action, tf);
+	    if (!callback[action](action,trap_frame)) hang(action, trap_frame);
 	}
 	break;
 
+    case 5:
+        /* EE -- Try to get a serial interrupt if debugging enabled, then fall
+         * back to primary handler 
+         */
+        if (!SerialInterrupt(action, trap_frame)) 
+            callback[action](action, trap_frame);
+        else
+            trap_frame->srr1 |= 0x8000;
+        break;
     case 0:
     case 2:
-    case 5:
     case 6:
     case 7:
     case 8:
     case 9:
     case 0xa:
-        if (!callback[action](action,tf)) hang(action, tf);
-        break;
-
+    case 0xc:
     case 0x20:
-        // Single step
-        TakeException(action, tf);
+        if (!callback[action](action,trap_frame)) hang(action, trap_frame);
         break;
 
         /* MMU Functions */
     case 0x100:
 	initme();
+        trap_frame->srr1 |= 0x8000;
 	break;
     case 0x101:
 	ret = mmuaddpage(arg1, (int)arg2);
@@ -161,7 +168,7 @@ int _mmumain(int action, void *arg1, void *arg2, void *arg3, void *tf)
         SerialSetUp((int)arg1, arg2, 9600);
         break;
     case 0x201:
-        TakeException((int)arg1, (int *)trap_frame);
+        TakeException((int)arg1, trap_frame);
         break;
 
     default:
@@ -251,7 +258,7 @@ int hang(int trapCode, ppc_trap_frame_t *trap)
         GdbAttach = 1;
         SerialSetUp(0, (void *)0x800003f8, 9600);
     }
-    TakeException(trapCode, (int *)trap);
+    while(1) SerialInterrupt(trapCode, trap);
     return 1;
 }
 
@@ -294,11 +301,17 @@ void initme()
             copy_trap_handler(i);
     }
 
+    /* Serial Interrupt */
+    callback[5] = SerialInterrupt;
+
     /* Floating point exception */
     callback[8] = fpenable;
 
     /* Ignore decrementer and EE */
     callback[9] = ignore;
+
+    /* Single Step */
+    callback[0x20] = TakeException;
 }
 
 ppc_map_t *allocpage()