diff --git a/ChangeLog b/ChangeLog
index b10f742cc1a..5713a1e8768 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -4375,3 +4375,8 @@
 	* arch/arm/src/armv7-h/ram_vectors.h, up_ramvec_*.c, arch/arm/src/*/*_irq.c,
 	  and Make.defs:  Add support for modifiable interrupt vectors in RAM
       (2013-03-18).
+	* arch/arm/src/armv7-m/up_exception.S, sam3u/sam3u_vectors.S, and
+	  lpc17xx/lpc17_vectors.S: In exception handling with CONFIG_NUTTX_KERNEL,
+	  need to explicity set and cleare the privilege bit in the CONTROL
+	  register on return.  I assumed this would be handled automatically
+	  by the EXC_RETURN.  Silly me (2013-03-18).
diff --git a/arch/arm/src/armv7-m/up_exception.S b/arch/arm/src/armv7-m/up_exception.S
index 35d9231871f..df7a7ad2997 100644
--- a/arch/arm/src/armv7-m/up_exception.S
+++ b/arch/arm/src/armv7-m/up_exception.S
@@ -201,10 +201,30 @@ exception_common:
 	/* The EXC_RETURN value tells us whether we are returning on the MSP or PSP 
 	 */
 
+#ifdef CONFIG_NUTTX_KERNEL
+	/* The EXC_RETURN value will be 0xfffffff9 (privileged thread) or 0xfffffff1
+	 * (handler mode) if the stack is on the MSP.  It can only be on the PSP if
+	 * EXC_RETURN is 0xfffffffd (unprivileged thread)
+	 */
+
+	mrs		r2, control				/* R2=Contents of the control register */
+	tst		r14, #EXC_RETURN_PROCESS_STACK /* nonzero if context on process stack */
+	beq		3f						/* Branch if privileged */
+
+	orr		r2, r2, #1				/* Unprivileged mode */
+	msr		psp, r1					/* R1=The process stack pointer */
+	b		4f
+3:
+	bic		r2, r2, #1				/* Privileged mode */
+	msr		msp, r1					/* R1=The main stack pointer */
+4:
+	msr		control, r2				/* Save the updated control register */
+#else
 	tst		r14, #EXC_RETURN_PROCESS_STACK /* nonzero if context on process stack */
 	ite		eq						/* next two instructions conditional */
 	msreq	msp, r1					/* R1=The main stack pointer */
 	msrne	psp, r1					/* R1=The process stack pointer */
+#endif
 
 	/* Restore the interrupt state */
 
diff --git a/arch/arm/src/lpc17xx/lpc17_vectors.S b/arch/arm/src/lpc17xx/lpc17_vectors.S
index eca382b1b1c..9575e1f3ec1 100644
--- a/arch/arm/src/lpc17xx/lpc17_vectors.S
+++ b/arch/arm/src/lpc17xx/lpc17_vectors.S
@@ -43,6 +43,7 @@
 #include <arch/irq.h>
 
 #include "chip.h"
+#include "exc_return.h"
 
 /************************************************************************************************
  * Preprocessor Definitions
@@ -209,7 +210,7 @@ lpc17_common:
 
 #ifdef CONFIG_NUTTX_KERNEL
 	/* The EXC_RETURN value will be 0xfffffff9 (privileged thread) or 0xfffffff1
-	 * (handler mode) if the state is on the MSP.  It can only be on the PSP if
+	 * (handler mode) if the stack is on the MSP.  It can only be on the PSP if
 	 * EXC_RETURN is 0xfffffffd (unprivileged thread)
 	 */
 
@@ -351,16 +352,25 @@ lpc17_common:
 	 *   r4-r11 = restored register values
 	 */
 2:
+
 #ifdef CONFIG_NUTTX_KERNEL
 	/* The EXC_RETURN value will be 0xfffffff9 (privileged thread) or 0xfffffff1
-	 * (handler mode) if the state is on the MSP.  It can only be on the PSP if
+	 * (handler mode) if the stack is on the MSP.  It can only be on the PSP if
 	 * EXC_RETURN is 0xfffffffd (unprivileged thread)
 	 */
 
-	adds	r0, r14, #3				/* If R14=0xfffffffd, then r0 == 0 */
-	ite		ne						/* Next two instructions are condition */
-	msrne	msp, r1					/* R1=The main stack pointer */
-	msreq	psp, r1					/* R1=The process stack pointer */
+	mrs		r2, control				/* R2=Contents of the control register */
+	tst		r14, #EXC_RETURN_PROCESS_STACK /* nonzero if context on process stack */
+	beq		3f						/* Branch if privileged */
+
+	orr		r2, r2, #1				/* Unprivileged mode */
+	msr		psp, r1					/* R1=The process stack pointer */
+	b		4f
+3:
+	bic		r2, r2, #1				/* Privileged mode */
+	msr		msp, r1					/* R1=The main stack pointer */
+4:
+	msr		control, r2				/* Save the updated control register */
 #else
 	msr		msp, r1					/* Recover the return MSP value */
 
diff --git a/arch/arm/src/sam3u/sam3u_vectors.S b/arch/arm/src/sam3u/sam3u_vectors.S
index eba6edd3ae0..baaeb54b957 100644
--- a/arch/arm/src/sam3u/sam3u_vectors.S
+++ b/arch/arm/src/sam3u/sam3u_vectors.S
@@ -42,6 +42,8 @@
 
 #include <arch/irq.h>
 
+#include "exc_return.h"
+
 /************************************************************************************************
  * Preprocessor Definitions
  ************************************************************************************************/
@@ -236,7 +238,7 @@ sam3u_common:
 
 #ifdef CONFIG_NUTTX_KERNEL
 	/* The EXC_RETURN value will be 0xfffffff9 (privileged thread) or 0xfffffff1
-	 * (handler mode) if the state is on the MSP.  It can only be on the PSP if
+	 * (handler mode) if the stack is on the MSP.  It can only be on the PSP if
 	 * EXC_RETURN is 0xfffffffd (unprivileged thread)
 	 */
 
@@ -378,16 +380,25 @@ sam3u_common:
 	 *   r4-r11 = restored register values
 	 */
 2:
+
 #ifdef CONFIG_NUTTX_KERNEL
 	/* The EXC_RETURN value will be 0xfffffff9 (privileged thread) or 0xfffffff1
-	 * (handler mode) if the state is on the MSP.  It can only be on the PSP if
+	 * (handler mode) if the stack is on the MSP.  It can only be on the PSP if
 	 * EXC_RETURN is 0xfffffffd (unprivileged thread)
 	 */
 
-	adds	r0, r14, #3				/* If R14=0xfffffffd, then r0 == 0 */
-	ite		ne						/* Next two instructions are condition */
-	msrne	msp, r1					/* R1=The main stack pointer */
-	msreq	psp, r1					/* R1=The process stack pointer */
+	mrs		r2, control				/* R2=Contents of the control register */
+	tst		r14, #EXC_RETURN_PROCESS_STACK /* nonzero if context on process stack */
+	beq		3f						/* Branch if privileged */
+
+	orr		r2, r2, #1				/* Unprivileged mode */
+	msr		psp, r1					/* R1=The process stack pointer */
+	b		4f
+3:
+	bic		r2, r2, #1				/* Privileged mode */
+	msr		msp, r1					/* R1=The main stack pointer */
+4:
+	msr		control, r2				/* Save the updated control register */
 #else
 	msr		msp, r1					/* Recover the return MSP value */