Index: src/nci_test.c
===================================================================
--- src/nci_test.c	(revision 38164)
+++ src/nci_test.c	(working copy)
@@ -104,7 +104,7 @@
 PARROT_EXPORT void   nci_vpii(Outer *, int, int);
 PARROT_EXPORT void   nci_vv(void);
 PARROT_EXPORT void   nci_vVi(Opaque**, int);
-PARROT_EXPORT void   nci_vp(Opaque*);
+PARROT_EXPORT void   nci_vp(Opaque**);
 PARROT_EXPORT char * nci_ttt(char *, char *);
 PARROT_EXPORT void   nci_vfff(float, float, float);
 PARROT_EXPORT void   nci_vV(const char **);
@@ -1087,7 +1087,7 @@
 /*
 
 =item C<PARROT_EXPORT int
-nci_vp(Opaque*)>
+nci_vp(Opaque**)>
 
 Test that a previously generated opaque struct gets passed back
 to an NCI function correctly.
@@ -1097,10 +1097,10 @@
 */
 
 PARROT_EXPORT void
-nci_vp(Opaque *inOpaque)
+nci_vp(Opaque **inOpaque)
 {
-    if (inOpaque)
-        printf("got %d\n", inOpaque->x);
+    if (*inOpaque)
+        printf("got %d\n", (*inOpaque)->x);
     else
         printf("got null");
 }
Index: src/pmc/pointer.pmc
===================================================================
--- src/pmc/pointer.pmc	(revision 38164)
+++ src/pmc/pointer.pmc	(working copy)
@@ -23,8 +23,8 @@
 #include "parrot/parrot.h"
 
 pmclass Pointer need_ext {
-    ATTR void * mark_function;
-    ATTR void * pointer;
+    ATTR void  * mark_function;
+    ATTR void ** pointer;
 
 /*
 
@@ -69,7 +69,7 @@
     VTABLE void mark() {
         void (*mark_function)(Interp *, void *) =
             (void (*)(Interp *, void *))D2FPTR(PARROT_POINTER(SELF)->mark_function);
-        void * data = PARROT_POINTER(SELF)->pointer;
+        void * data = *PARROT_POINTER(SELF)->pointer;
         if (data && mark_function)
             (*mark_function)(INTERP, data);
     }
@@ -102,7 +102,7 @@
 */
 
     VTABLE void set_pointer(void *ptr) {
-        PARROT_POINTER(SELF)->pointer = ptr;
+        *PARROT_POINTER(SELF)->pointer = ptr;
     }
 
 /*
@@ -116,7 +116,7 @@
 */
 
     VTABLE void *get_pointer() {
-        return PARROT_POINTER(SELF)->pointer;
+        return &(PARROT_POINTER(SELF)->pointer);
     }
 
 /*
@@ -130,7 +130,7 @@
 */
 
     VTABLE INTVAL get_integer() {
-        return (INTVAL)(PARROT_POINTER(SELF)->pointer);
+        return (INTVAL)&(PARROT_POINTER(SELF)->pointer);
     }
 
 /*
@@ -144,7 +144,7 @@
 */
 
     VTABLE FLOATVAL get_number() {
-        return (FLOATVAL)(INTVAL)(PARROT_POINTER(SELF)->pointer);
+        return (FLOATVAL)(INTVAL)&(PARROT_POINTER(SELF)->pointer);
     }
 
 /*
@@ -158,7 +158,7 @@
 */
 
     VTABLE STRING *get_repr() {
-        return Parrot_sprintf_c(INTERP, "Pointer = 0x%p", PARROT_POINTER(SELF)->pointer);
+        return Parrot_sprintf_c(INTERP, "Pointer = 0x%p", &PARROT_POINTER(SELF)->pointer);
     }
 
 
@@ -166,7 +166,7 @@
 
 =item C<STRING *get_string()>
 
-Returns the pointer value as a Parrot string.
+Returns the pointer value as a Parrot C<STRING*>.
 
 =cut
 
@@ -187,7 +187,7 @@
 */
 
     VTABLE INTVAL get_bool() {
-        return (INTVAL)(PMC_data(SELF) != NULL);
+        return (INTVAL)(*PARROT_POINTER(SELF)->pointer != NULL);
     }
 
 /*
Index: src/jit/i386/jit_defs.c
===================================================================
--- src/jit/i386/jit_defs.c	(revision 38164)
+++ src/jit/i386/jit_defs.c	(working copy)
@@ -2273,6 +2273,9 @@
                 emitm_movl_m_r(interp, pc, emit_EAX, emit_EAX, 0, 1, offsetof(VTABLE, get_pointer));
                 emitm_callr(pc, emit_EAX);
                 emitm_movl_r_m(interp, pc, emit_EAX, emit_EBP, 0, 1, args_offset);
+                /* reset ESP(4) */
+                emitm_lea_m_r(interp, pc, emit_EAX, emit_EBP, 0, 1, st_offset);
+                emitm_movl_r_m(interp, pc, emit_EAX, emit_EBP, 0, 1, temp_calls_offset + 4);
                 break;
             case 'b':   /* buffer (void*) pass PObj_bufstart(SReg) */
                 emitm_call_cfunc(pc, get_nci_S);
Index: t/pmc/nci.t
===================================================================
--- t/pmc/nci.t	(revision 38168)
+++ t/pmc/nci.t	(working copy)
@@ -2647,11 +2647,6 @@
 3
 OUTPUT
 
-{
-    local $TODO = 0;
-    if ($PConfig{jitcapable}){
-        $TODO = "TT #551 - jitted NCI sig with V is broken";
-    }
 pir_output_is( << 'CODE', << 'OUTPUT', "nci_vVi - void** out parameter" );
 .sub test :main
     .local string library_name
@@ -2674,7 +2669,6 @@
 CODE
 got 10
 OUTPUT
-}
 
 pir_output_is( << 'CODE', << 'OUTPUT', "nci_ttt - t_tt parameter" );
 .sub test :main
@@ -2712,11 +2706,6 @@
 1
 OUTPUT
 
-{
-    local $TODO = 0;
-    if ($PConfig{jitcapable}){
-        $TODO = "TT #551 - jitted NCI sig with V is broken";
-    }
 pir_output_is( << 'CODE', << 'OUTPUT', "nci_vV - char** out parameter" );
 .sub test :main
     .local string library_name
@@ -2764,7 +2753,6 @@
 It is a beautiful day!
 Go suck a lemon.
 OUTPUT
-}
 
 # Local Variables:
 #   mode: cperl
Index: tools/build/nativecall.pl
===================================================================
--- tools/build/nativecall.pl	(revision 38164)
+++ tools/build/nativecall.pl	(working copy)
@@ -353,11 +353,10 @@
     };
     /V/ && do {
         push @{$temps_ref},          "PMC *t_$temp_num;";
-        push @{$temps_ref},          "void *v_$temp_num;";
+        push @{$temps_ref},          "void **v_$temp_num;";
         push @{$extra_preamble_ref}, "t_$temp_num = GET_NCI_P($reg_num);";
-        push @{$extra_preamble_ref}, "v_$temp_num = VTABLE_get_pointer(interp, t_$temp_num);";
-        push @{$extra_postamble_ref}, "VTABLE_set_pointer(interp, t_$temp_num, v_$temp_num);";
-        return "&v_$temp_num";
+        push @{$extra_preamble_ref}, "v_$temp_num = (void **) VTABLE_get_pointer(interp, t_$temp_num);";
+        return "v_$temp_num";
     };
     /[ilIscfdNS]/ && do {
         my $ret_type = $sig_table{$_}{return_type};