Index: generic/gentclAPI.decls
===================================================================
diff -u -rbf592f968ae84740d9ef7c40cddbcbf9f5a68283 -rb01ae78fb55550ee1ce97f2c8c69a07535190411
--- generic/gentclAPI.decls	(.../gentclAPI.decls)	(revision bf592f968ae84740d9ef7c40cddbcbf9f5a68283)
+++ generic/gentclAPI.decls	(.../gentclAPI.decls)	(revision b01ae78fb55550ee1ce97f2c8c69a07535190411)
@@ -157,6 +157,10 @@
   {-argName "varName" -required 1 -type tclobj}
   {-argName "value" -required 0 -type tclobj}
 }
+cmd "var::unset" NsfUnsetVarCmd {
+  {-argName "object" -required 1 -type object}
+  {-argName "varName" -required 1 -type tclobj}
+}
 
 #
 # object methods
Index: generic/nsf.c
===================================================================
diff -u -rd40717ac3710f2123cb9359e3d0442ad4ff3da73 -rb01ae78fb55550ee1ce97f2c8c69a07535190411
--- generic/nsf.c	(.../nsf.c)	(revision d40717ac3710f2123cb9359e3d0442ad4ff3da73)
+++ generic/nsf.c	(.../nsf.c)	(revision b01ae78fb55550ee1ce97f2c8c69a07535190411)
@@ -12112,7 +12112,36 @@
   return TCL_ERROR;
 }
 
+/*
+ *----------------------------------------------------------------------
+ * UnsetInstVar --
+ *
+ *    Unset an instance variable of the specified object.
+ *
+ * Results:
+ *    Tcl result code.
+ *
+ * Side effects:
+ *    Variable unset.
+ *
+ *----------------------------------------------------------------------
+ */
 static int
+UnsetInstVar(Tcl_Interp *interp, NsfObject *object, CONST char* name) {
+  CallFrame frame, *framePtr = &frame;
+  int flags, result;
+
+  assert(object);
+  flags = (object->nsPtr) ? TCL_LEAVE_ERR_MSG|TCL_NAMESPACE_ONLY : TCL_LEAVE_ERR_MSG;
+
+  Nsf_PushFrameObj(interp, object, framePtr);
+  result = Tcl_UnsetVar2(interp, name, NULL, flags);
+  Nsf_PopFrameObj(interp, framePtr);
+
+  return result;
+}
+
+static int
 NsfSetterMethod(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]) {
   SetterCmdClientData *cd = (SetterCmdClientData*)clientData;
   NsfObject *object = cd->object;
@@ -16576,6 +16605,23 @@
 }
 
 /*
+nsfCmd var::unset NsfUnsetVarCmd {
+  {-argName "object" -required 1 -type object}
+  {-argName "varname" -required 1 -type tclobj}
+}
+*/
+static int
+NsfUnsetVarCmd(Tcl_Interp *interp, NsfObject *object, Tcl_Obj *varNameObj) {
+  char *varName = ObjStr(varNameObj);
+
+  if (CheckVarName(interp, varName) != TCL_OK) {
+    return TCL_ERROR;
+  }
+  
+  return UnsetInstVar(interp, object, varName);
+}
+
+/*
 nsfCmd method::setter NsfSetterCmd {
   {-argName "object" -required 1 -type object}
   {-argName "-per-object"}
Index: generic/nsf.h
===================================================================
diff -u -rd40717ac3710f2123cb9359e3d0442ad4ff3da73 -rb01ae78fb55550ee1ce97f2c8c69a07535190411
--- generic/nsf.h	(.../nsf.h)	(revision d40717ac3710f2123cb9359e3d0442ad4ff3da73)
+++ generic/nsf.h	(.../nsf.h)	(revision b01ae78fb55550ee1ce97f2c8c69a07535190411)
@@ -257,7 +257,7 @@
 		 Tcl_Obj *cmdNameObj, Tcl_Obj *methodObj);
 
 extern int
-NsfNoDispatchObjectError(Tcl_Interp *interp, char *methodName);
+NsfNoDispatchObjectError(Tcl_Interp *interp, CONST char *methodName);
 
 #define NSF_LOG_NOTICE 2
 #define NSF_LOG_WARN 1
Index: generic/nsfError.c
===================================================================
diff -u -rd40717ac3710f2123cb9359e3d0442ad4ff3da73 -rb01ae78fb55550ee1ce97f2c8c69a07535190411
--- generic/nsfError.c	(.../nsfError.c)	(revision d40717ac3710f2123cb9359e3d0442ad4ff3da73)
+++ generic/nsfError.c	(.../nsfError.c)	(revision b01ae78fb55550ee1ce97f2c8c69a07535190411)
@@ -203,7 +203,7 @@
  *----------------------------------------------------------------------
  */
 int
-NsfNoDispatchObjectError(Tcl_Interp *interp, char *methodName) {
+NsfNoDispatchObjectError(Tcl_Interp *interp, CONST char *methodName) {
   return NsfPrintError(interp, "Method %s not dispatched on object; "
 		       "don't call aliased methods via namespace paths!",
 		       methodName);
Index: generic/tclAPI.h
===================================================================
diff -u -r65abda7763aa24fe8a33728195cc3043d06ee660 -rb01ae78fb55550ee1ce97f2c8c69a07535190411
--- generic/tclAPI.h	(.../tclAPI.h)	(revision 65abda7763aa24fe8a33728195cc3043d06ee660)
+++ generic/tclAPI.h	(.../tclAPI.h)	(revision b01ae78fb55550ee1ce97f2c8c69a07535190411)
@@ -233,6 +233,7 @@
 static int NsfSetVarCmdStub(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv []);
 static int NsfSetterCmdStub(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv []);
 static int NsfShowStackCmdStub(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv []);
+static int NsfUnsetVarCmdStub(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv []);
 static int NsfOAutonameMethodStub(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv []);
 static int NsfOClassMethodStub(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv []);
 static int NsfOCleanupMethodStub(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv []);
@@ -320,6 +321,7 @@
 static int NsfSetVarCmd(Tcl_Interp *interp, NsfObject *object, Tcl_Obj *varName, Tcl_Obj *value);
 static int NsfSetterCmd(Tcl_Interp *interp, NsfObject *object, int withPer_object, Tcl_Obj *parameter);
 static int NsfShowStackCmd(Tcl_Interp *interp);
+static int NsfUnsetVarCmd(Tcl_Interp *interp, NsfObject *object, Tcl_Obj *varName);
 static int NsfOAutonameMethod(Tcl_Interp *interp, NsfObject *obj, int withInstance, int withReset, Tcl_Obj *name);
 static int NsfOClassMethod(Tcl_Interp *interp, NsfObject *obj, Tcl_Obj *class);
 static int NsfOCleanupMethod(Tcl_Interp *interp, NsfObject *obj);
@@ -408,6 +410,7 @@
  NsfSetVarCmdIdx,
  NsfSetterCmdIdx,
  NsfShowStackCmdIdx,
+ NsfUnsetVarCmdIdx,
  NsfOAutonameMethodIdx,
  NsfOClassMethodIdx,
  NsfOCleanupMethodIdx,
@@ -1490,6 +1493,26 @@
 }
 
 static int
+NsfUnsetVarCmdStub(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]) {
+  ParseContext pc;
+  (void)clientData;
+
+  if (ArgumentParse(interp, objc, objv, NULL, objv[0], 
+                     method_definitions[NsfUnsetVarCmdIdx].paramDefs, 
+                     method_definitions[NsfUnsetVarCmdIdx].nrParameters, 1,
+                     &pc) != TCL_OK) {
+    return TCL_ERROR;
+  } else {
+    NsfObject *object = (NsfObject *)pc.clientData[0];
+    Tcl_Obj *varName = (Tcl_Obj *)pc.clientData[1];
+
+    assert(pc.status == 0);
+    return NsfUnsetVarCmd(interp, object, varName);
+
+  }
+}
+
+static int
 NsfOAutonameMethodStub(ClientData clientData, Tcl_Interp *interp, int objc, Tcl_Obj *CONST objv[]) {
   ParseContext pc;
   NsfObject *obj =  (NsfObject *)clientData;
@@ -2341,6 +2364,10 @@
 {"::nsf::__db_show_stack", NsfShowStackCmdStub, 0, {
   {NULL, 0, 0, NULL, NULL,NULL,NULL,NULL,NULL,NULL,NULL}}
 },
+{"::nsf::var::unset", NsfUnsetVarCmdStub, 2, {
+  {"object", NSF_ARG_REQUIRED, 0, Nsf_ConvertToObject, NULL,NULL,NULL,NULL,NULL,NULL,NULL},
+  {"varName", NSF_ARG_REQUIRED, 0, Nsf_ConvertToTclobj, NULL,NULL,NULL,NULL,NULL,NULL,NULL}}
+},
 {"::nsf::methods::object::autoname", NsfOAutonameMethodStub, 3, {
   {"-instance", 0, 0, Nsf_ConvertToString, NULL,NULL,NULL,NULL,NULL,NULL,NULL},
   {"-reset", 0, 0, Nsf_ConvertToString, NULL,NULL,NULL,NULL,NULL,NULL,NULL},