Index: generic/nsfObj.c
===================================================================
diff -u -N -r24cc5e107fd8d246061a9d4b4fafefc767811c2b -reea18b07ddfc917545d48ab6a272c0bfb9656f07
--- generic/nsfObj.c	(.../nsfObj.c)	(revision 24cc5e107fd8d246061a9d4b4fafefc767811c2b)
+++ generic/nsfObj.c	(.../nsfObj.c)	(revision eea18b07ddfc917545d48ab6a272c0bfb9656f07)
@@ -26,6 +26,8 @@
  */
 
 #include "nsfInt.h"
+#include "nsfAccessInt.h"
+
 /*
  *----------------------------------------------------------------------
  *
@@ -405,7 +407,7 @@
     register Tcl_Obj *objPtr)	/* The object to convert. */
 {
   NsfClass *mixin = NULL;
-  Tcl_Obj *guardObj = NULL, *nameObj;
+  Tcl_Obj *guardObj = NULL, *nameObj = NULL;
   Mixinreg *mixinRegPtr;
   int oc; Tcl_Obj **ov;
 
@@ -414,20 +416,20 @@
     if (oc == 1) {
       nameObj = ov[0];
 
-    } else if (oc == 2) {
+      /*} else if (oc == 2) {
       nameObj = ov[0];
-      guardObj = ov[1];
+      guardObj = ov[1];*/
 
     } else if (oc == 3 && !strcmp(ObjStr(ov[1]), NsfGlobalStrings[NSF_GUARD_OPTION])) {
       nameObj = ov[0];
       guardObj = ov[2];
 
     } else {
-      return TCL_ERROR;
+      nameObj = objPtr;
     }
 
   } else {
-    return TCL_ERROR;
+    return NsfObjErrType(interp, "mixin", nameObj, "a class as mixin", NULL);
   }
 
   /*
@@ -484,14 +486,30 @@
  */
 
 int
-NsfMixinregGet(Tcl_Obj *obj, NsfClass **clPtr, Tcl_Obj **guardObj) {
+NsfMixinregGet(Tcl_Interp *interp, Tcl_Obj *obj, NsfClass **clPtr, Tcl_Obj **guardObj) {
 
+  assert(interp);
   assert(obj);
   assert(clPtr); 
   assert(guardObj);
 
   if (obj->typePtr == &NsfMixinregObjType) {
     Mixinreg *mixinRegPtr = obj->internalRep.twoPtrValue.ptr1;
+
+    /*
+     * We got a cmd, but this might be already deleted.
+     */
+    if ((Tcl_Command_flags(mixinRegPtr->mixin->object.id) & CMD_IS_DELETED)) {
+      /*
+       * The cmd is deleted. retry to refetch it.
+       */
+      if (MixinregSetFromAny(interp, obj) == TCL_OK) {
+	mixinRegPtr = obj->internalRep.twoPtrValue.ptr1;
+      } else {
+	return TCL_ERROR;
+      }
+    }
+
     *guardObj = mixinRegPtr->guardObj;
     *clPtr = mixinRegPtr->mixin;
     return TCL_OK;
@@ -610,9 +628,9 @@
     if (oc == 1) {
       filterObj = ov[0];
 
-    } else if (oc == 2) {
+      /*    } else if (oc == 2) {
       filterObj = ov[0];
-      guardObj = ov[1];
+      guardObj = ov[1];*/
 
     } else if (oc == 3 && !strcmp(ObjStr(ov[1]), NsfGlobalStrings[NSF_GUARD_OPTION])) {
       filterObj = ov[0];
@@ -672,7 +690,7 @@
  */
 
 int
-NsfFilterregGet(Tcl_Obj *obj, Tcl_Obj **filterObj, Tcl_Obj **guardObj) {
+NsfFilterregGet(Tcl_Interp *UNUSED(interp), Tcl_Obj *obj, Tcl_Obj **filterObj, Tcl_Obj **guardObj) {
 
   assert(obj);
   assert(filterObj);