diff --git a/stix/kernel/Context.st b/stix/kernel/Context.st
index 9e87b16..0e42531 100644
--- a/stix/kernel/Context.st
+++ b/stix/kernel/Context.st
@@ -7,7 +7,7 @@
 
 #class(#pointer) Context(Apex)
 {
-	#dcl sender ip sp ntmprs.
+	#dcl sender ip sp ntmprs ensure_block.
 
 	#method sender
 	{
@@ -75,6 +75,8 @@
 
 	#method findExceptionHandlerBlock: anExceptionClass
 	{
+		## find an exception handler block for a given exception class.
+		##
 		## for this to work, self must be an exception handler context.
 		## For a single on:do: call,
 		##   self class specNumInstVars must return 8.
@@ -85,7 +87,9 @@
 			| bound exc |
 			## NOTE: if on:do: has a temporary varible, bound must be adjusted to reflect it.
 			bound := self basicSize - 1.
-			8 to: bound by: 2 do: [ :i | 
+## TODO: change 9 to a constant when stix is enhanced to support constant definition
+##       or calcuate the minimum size using the class information.
+			9 to: bound by: 2 do: [ :i | 
 				exc := self basicAt: i.
 				((anExceptionClass == exc) or: [anExceptionClass inheritsFrom: exc]) ifTrue: [^self basicAt: (i + 1)].
 			]
@@ -330,6 +334,7 @@ thisContext isExceptionHandlerContext dump.
 	{
 ## TODO: ensure that the ensured block is executed after exception handler...
 		| v |
+		self.ensure_block := aBlock.
 		v := self on: Exception do: [:ex | 
 			aBlock value.
 			ex pass
diff --git a/stix/kernel/test-010.st b/stix/kernel/test-010.st
index 86744dd..9d06d09 100644
--- a/stix/kernel/test-010.st
+++ b/stix/kernel/test-010.st
@@ -111,7 +111,25 @@
 "
 
 	}
-	
+
+	#method(#class) aaa_123
+	{
+		| v1 |
+		v1 := [
+			| k |
+			k := 99.
+			[
+				[
+					##[ Exception signal: 'simulated error' ] ensure: [('ensure 1 ', (k asString)) dump ].
+					[ ^20 ] ensure: [('ensure 1 ', (k asString)) dump ].
+				] ensure: ['ensure 2' dump ].
+			] ensure: ['ensure 3' dump ].
+		] on: Exception do: [:ex | 
+			('EXCETION - ' , ex messageText) dump.
+			## Exception signal: 'qqq'.
+		].
+		^v1
+	}
 	#method(#class) main
 	{
 		| v1 |
@@ -131,17 +149,21 @@
 
 		"[1 xxx] ifCurtailed: ['XXXXXXXX CURTAILED XXXXXXXXX' dump. Exception signal: 'jjjj']."
 
-		v1 := [
+"		v1 := [
 			| k |
 			k := 99.
 			[
-				[ Exception signal: 'simulated error' ] ensure: [('ensure 1 ', (k asString)) dump ].
-			] ensure: ['ensure 2' dump ].
+				[
+					##[ Exception signal: 'simulated error' ] ensure: [('ensure 1 ', (k asString)) dump ].
+					[ ^20 ] ensure: [('ensure 1 ', (k asString)) dump ].
+				] ensure: ['ensure 2' dump ].
+			] ensure: ['ensure 3' dump ].
 		] on: Exception do: [:ex | 
 			('EXCETION - ' , ex messageText) dump.
 			## Exception signal: 'qqq'.
 		].
-
+"
+		v1 := self aaa_123.
 		'--------------------------------' dump.
 		v1 dump.
 		'END OF MAIN' dump.
diff --git a/stix/lib/exec.c b/stix/lib/exec.c
index 723bccd..2dda872 100644
--- a/stix/lib/exec.c
+++ b/stix/lib/exec.c
@@ -1672,6 +1672,7 @@ printf ("PRIM BlockContext value FAIL - NARGS MISMATCH\n");
 #else
 	blkctx->ip = rcv_blkctx->ip;
 	blkctx->ntmprs = rcv_blkctx->ntmprs;
+	blkctx->ensure_block = rcv_blkctx->ensure_block;
 	blkctx->method_or_nargs = rcv_blkctx->method_or_nargs;
 	blkctx->receiver_or_source = (stix_oop_t)rcv_blkctx;
 	blkctx->home = rcv_blkctx->home;
@@ -3838,7 +3839,23 @@ return -1;
 				 */
 				stix->ip--; 
 			#else
-				if (stix->active_context->origin == stix->processor->active->initial_context->origin)
+				if ((stix_oop_t)stix->active_context->ensure_block != stix->_nil)
+				{
+STIX_LOG0 (stix, STIX_LOG_ERROR, "ABOUT TO EVALUATE ENSURE BLOCK ....\n");
+					STIX_STACK_PUSH (stix, (stix_oop_t)stix->active_context->ensure_block);
+
+stix->active_context->ensure_block = (stix_oop_context_t)stix->_nil;
+stix->ip--;
+					if (prim_block_value (stix, 0) <= 0)
+					{
+						/* TODO: problems in evaluating an ensure-block */
+						/* TODO: ..... */
+						STIX_STACK_POP (stix);
+STIX_LOG0 (stix, STIX_LOG_ERROR, "ERROR ENSURE BLOCK FAILURE....\n");
+					}
+					
+				}
+				else if (stix->active_context->origin == stix->processor->active->initial_context->origin)
 				{
 					/* method return from a processified block
 					 * 
@@ -3924,7 +3941,7 @@ return -1;
 						/* NOTE: this condition is true for the processified block context also.
 						 *   stix->active_context->origin == stix->processor->active->initial_context->origin
 						 *   however, the check here is done after context switching and the
-						 *   processified block check is done against the context before switching */
+						 *   processified block check has been done against the context before switching */
 
 						/* the stack contains the final return value so the stack pointer must be 0. */
 						STIX_ASSERT (stix->sp == 0); 
diff --git a/stix/lib/stix.h b/stix/lib/stix.h
index 2816b4b..17e71bc 100644
--- a/stix/lib/stix.h
+++ b/stix/lib/stix.h
@@ -513,7 +513,7 @@ struct stix_method_t
 #define STIX_METHOD_PREAMBLE_INDEX_MAX 0xFFFF
 #define STIX_OOI_IN_METHOD_PREAMBLE_INDEX_RANGE(num) ((num) >= STIX_METHOD_PREAMBLE_INDEX_MIN && (num) <= STIX_METHOD_PREAMBLE_INDEX_MAX)
 
-#define STIX_CONTEXT_NAMED_INSTVARS 8
+#define STIX_CONTEXT_NAMED_INSTVARS 9
 typedef struct stix_context_t stix_context_t;
 typedef struct stix_context_t* stix_oop_context_t;
 struct stix_context_t
@@ -540,6 +540,9 @@ struct stix_context_t
 	 * defined its 'home'. */
 	stix_oop_t          ntmprs;
 
+	/* **** */
+	stix_oop_context_t  ensure_block; 
+
 	/* CompiledMethod for a method context, 
 	 * SmallInteger for a block context */
 	stix_oop_t          method_or_nargs;